What do we know about mystery drones flying over New Jersey ...

Mysterious drone sightings in New Jersey, New York, Pennsylvania and other East Coast states have prompted an outcry from officials seeking answers about the flying objects, some of which have been spotted near military installations.

A federal official said Thursday that the FBI is the lead agency investigating the sightings. An FBI official told CBS News the agency has received several thousand tips. Local law enforcement agencies are also investigating.

On Monday, the FBI, Department of Homeland Security, Federal Aviation Administration and Department of Defense said in a joint statement they "have not identified anything anomalous and do not assess the activity to date to present a national security or public safety risk."

Multiple sightings have been reported in parts of New Jersey, New York City, New York's suburban Rockland County and several counties in eastern Pennsylvania, Maryland, Connecticut and Massachusetts. The NYPD said Thursday that multiple drones were seen flying over a neighborhood in the Bronx, but soon after officers responded to calls about the sightings, the drones disappeared. 

And on Friday night, drone activity briefly shut down runways at Stewart International Airport in Orange County, New York, Gov. Kathy Hochul confirmed Saturday.  

Two people were arrested in Boston Saturday night for what police describe as a "hazardous drone operation" near Logan Airport.

White House national security adviser John Kirby said on "CBS Mornings" Tuesday that there's "absolutely no indication at this point that there's a national security threat or a public security threat" based on what's currently known. He added that the administration believes the "vast majority" of the sightings represent commercial drones, law enforcement drones, hobbyists and of civil aviation aircraft.

What have authorities said about the drone sightings?

On Monday, the FBI, Department of Homeland Security, Federal Aviation Administration and Defense Department released a joint statement, saying: "Having closely examined the technical data and tips from concerned citizens, we assess that the sightings to date include a combination of lawful commercial drones, hobbyist drones, and law enforcement drones, as well as manned fixed-wing aircraft, helicopters, and stars mistakenly reported as drones. We have not identified anything anomalous and do not assess the activity to date to present a national security or public safety risk over the civilian airspace in New Jersey or other states in the northeast."

The agencies added that they "recognize the concern among many communities" and "We urge Congress to enact counter-UAS legislation when it reconvenes that would extend and expand existing counter-drone authorities to identify and mitigate any threat that may emerge."

They said that reported sightings of drones near or over military installations "are not new. DoD takes unauthorized access over its airspace seriously and coordinates closely with federal, state, and local law enforcement authorities, as appropriate."

The FAA noted separately on social media that "In New York and New Jersey, there are thousands of daily drone operations."

Last week, in a letter to President Biden, New Jersey Gov. Phil Murphy called for more resources to be directed toward understanding what's behind the increased activity involving drones, also known as unmanned aircraft systems, or UAS.

"The continued reporting of UAS activity has raised more questions than answers and prompted an outcropping of conspiracy theories across social media and other platforms," Murphy said in a Thursday letter that he posted to social media Friday. "I respectfully urge you to continue to direct the federal agencies involved to work together until they uncover answers as to what is behind the UAS sightings."

During a call-in program on Wednesday night, Murphy said he would be bringing up the issue with the White House on Thursday but assured constituents that the drones as of now don't appear to pose a safety threat. 

"Based on everything we know," Murphy said, "there is no public safety risk we're aware of. On the other hand, is it frustrating to not have more answers on this? Is it frustrating to not have a source for these things? Yes."

Hochul announced Saturday that the runways at Stewart Airfield, which is a part of Stewart International Airport, were shut down for about one hour due to drone activity. The airport, located about 60 miles north of New York City, services commercial and military flights. 

She called on Congress to "pass the Counter-UAS Authority Security, Safety, and Reauthorization Act. This bill would reform legal authorities to counter-UAS and strengthen the FAA's oversight of drones, and would extend counter-UAS activities to select state and local law enforcement agencies."

Hochul said earlier Friday there was no evidence the drones posed a threat and that authorities were coordinating with the FBI, the Department of Homeland Security and other federal agencies. The New York State Police said it's received numerous reports of drone sightings and posted on social media an email address where people can submit additional reports.

In a statement Sunday, Hochul said federal officials are "deploying a state-of-the-art drone detection system to New York State."

An FBI official earlier this week told Congress that the FBI has received over 3,000 tips from the public about these incursions, which are mostly occurring at night.

On Wednesday, Senate Majority Leader Chuck Schumer, fellow New York Sen. Kirsten Gillibrand and New Jersey Sens. Cory Booker and Andy Kim sent a letter to DHS, the FBI and the Federal Aviation Administration requesting a briefing "as soon as possible on how your agencies are working with federal and local law enforcement to identify and address the source of these incursions."

Gillibrand told CBS News on Thursday, "We need the FAA and the FBI and Homeland Security to get on this. If they need authorities to take these drones down, they should ask for them, but I think they can take them down now because they don't know who is manning them."

Gillibrand said the drones can be taken down with traps or nets or disabled in other ways. 

"There's ways you can do this without endangering a population," she said. "At a minimum, you should be following these drones to see who's flying them and where they land, and then get them when they land."

Kim posted a video of what he saw over a New Jersey park Thursday night.

"I'm just not getting the kind of communication and engagement when it comes to the investigation that's happening by the FBI, Homeland Security, so we need a lot more communication to the people of New Jersey to be able to understand what's happening," Kim told CBS News New York.

And in a lengthy social media thread on Saturday, Kim claimed that "with the help of civilian pilots and others able to do deeper analysis" he "concluded that most of the possible drone sightings that were pointed out to me were almost certainly planes."

Kim said this conclusion was based, in part, on flight tracking data.

"I share this because this is the kind of analysis we need but are not getting from the federal government to explain this situation," Kim wrote Saturday. "FAA experts have much more experience/resources to identify aircraft. Instead I'm left to draw on civilian support and public apps."

The FAA said Thursday that at the request of federal partners, it had published two temporary flight restrictions prohibiting drone flights over Picatinny Arsenal Military Base and Trump National Golf Club Bedminster. 

Rep. Mike Waltz, a Republican from Florida who is President-elect Donald Trump's pick for national security adviser, said Sunday, "We need to know who's behind it. But right now, I think law enforcement seems to be...the Department of Homeland Security and the Defense Department are kind of doing this and pointing at each other."

Speaking on "Face the Nation with Margaret Brennan" on Sunday, Waltz said he believes the drone issue highlits lapses in authority between local law enforcement and federal agencies like the Department of Defense and Department of Homeland Security.

"I think Americans are finding it hard to believe we can't figure out where these are coming from," he added. "It's pointing to gaps in our capabilities and in our ability to clamp down on what's going on here. And we need to get to the bottom of it."

Sen. Amy Klobuchar, a Minnesota Democrat, in a separate interview Sunday on "Face the Nation" also called for "more transparency" and "new regulatory rules in place" for drone use.  

"We've got to figure out, do we really want all these drones? Because while these may be safe, who knows what happens in the future?" said Klobuchar. "They have to be within 400 feet [from the ground], so these things are going to be what? Flying over people's family picnics and over their homes and over beaches? This is not going to be a good future if we see too many of these."

Where have the drones been spotted?

The drones were first spotted near Morris County, in northern New Jersey, in mid-November. Since then, there have been reports in at least half a dozen states.

Low-flying drones have been spotted in numerous locations throughout the Garden State, over Staten Island, other areas of New York City, northwest of the city in Rockland County, several counties in Pennsylvania, Maryland, Connecticut and Massachusetts.

Former Maryland Gov. Larry Hogan said he "personally witnessed (and videoed) what appeared to be dozens of large drones in the sky above my residence in Davidsonville, Maryland (25 miles from our nation's capital). I observed the activity for approximately 45 minutes," beginning at about 9:45 p.m. Thursday night.

Hogan expressed frustration at the response from the federal government, calling it "entirely unacceptable." He also said that, "like many who have observed these drones," he didn't know if they posed a threat to public safety or national security.

"But the public is growing increasingly concerned and frustrated with the complete lack of transparency and the dismissive attitude of the federal government," Hogan said. "The government has the ability to track these from their point of origin but has mounted a negligent response. People are rightfully clamoring for answers, but aren't getting any."

CBS Philadelphia reports multiple drones flew into the airspace over Naval Weapons Station Earle, in Colts Neck, New Jersey. 

"While no direct threats to the installation have been identified, we can confirm multiple instances of unidentified drones entering the airspace above Naval Weapons Station Earle," a public affairs officer confirmed in a statement. "The base remains prepared to respond to any potential risks, leveraging robust security measures and advanced detection capabilities."

Multiple people reported to police drone activity over Cape Cod, Massachusetts, on Thursday night, according to CBS Boston. A resident in the Cape Cod town of Harwich told police she saw 10 to 15 drones over her house beginning at about 9 p.m. Thursday. 

"The resident could not hear the drones, but stated they were very bright, and she observed these for over an hour," Harwich Police Chief Kevin Considine said in a news release. 

Where are the drones coming from? 

"Our initial assessment is that this is not the work of a foreign adversary or a foreign entity," Pentagon deputy press secretary Sabrina Singh said on Wednesday.

After assessing that the drones are not a threat to military installations, the Pentagon is leaving it up to local law enforcement and the FBI to investigate the origins and type of drones. 

Singh said the drones were not U.S. military drones, and she refuted an idea presented by Rep. Jeff Van Drew of New Jersey that there was an Iranian "mothership" off the East Coast of the United States launching the drones. 

Why not shoot them down? 

Some lawmakers have called for shooting down the drones to analyze them, but others have voiced concern over falling debris endangering highly populated areas. 

Singh, the Pentagon deputy press secretary, said base commanders have the authority to shoot them down if they pose a threat to military installations, but so far, there hasn't been a threat. 

U.S. Northern Command, which oversees protecting the territory of the United States, said in a statement that it has not received requests from local law enforcement to assist. 

"We are aware and monitoring the reports of unauthorized drone flights in the vicinity of military installations in New Jersey to include Picatinny Arsenal and Naval Weapons Station Earle, and we refer you to those installations for information on any efforts they are may be conducting to ensure the safety and security of their personnel and operations," the statement said. 

Kirby acknowledged Tuesday that the administration needs "better authorities to close some of the gaps,"  including between the federal government and state governments. He noted that the president is calling on Congress to look into the issue amid a "brand new ecosystem of drones," saying, "we definitely need congressional help on this."

Is this a one-of-a-kind incident? 

This drone mystery comes on the heels of others in the past year or so. 

One of the most notable cases was in December 2023, Langley Air Force Base in Virginia reported multiple drone incursions throughout that December. In a statement at the time, the base said that the number of drones fluctuated and they ranged in size and configuration.

The head of U.S. Northern Command, or NORTHCOM, Gen. Gregory Guillot told Congress earlier this year during testimony that, "Drones are certainly an increasing threat. We see them on average reported that, that are detected in the NORTHCOM [area of responsibility] is anywhere from two to five a week over installations, military installations."

John Doyle, Alex Sundby and Andres Triay contributed to this report.

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