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Michael Catalini, Associated Press Michael Catalini, Associated Press

TRENTON, N.J. (AP) — A large number of mysterious drones have been reported flying over New Jersey and across the eastern U.S., sparking speculation and concern over where they came from and why.

New Jersey Gov. Phil Murphy and U.S. Sen. Andy Kim have both gone out on drone hunts, hoping for answers. The FBI, Homeland Security, state police and other agencies are investigating.

Murphy and law enforcement officials have stressed that the drones don't appear to be a threat to public safety, but many state and municipal lawmakers have nonetheless called for stricter rules about who can fly the unmanned aircraft — and to be allowed to shoot them out of the sky.

Dozens of witnesses have reported seeing drones statewide since mid-November, including near the Picatinny Arsenal, a military research and manufacturing facility, and over President-elect Donald Trump's golf course in Bedminster.

Murphy, a Democrat, said Monday that equipment supplied by the federal government has yielded little new information. He declined to describe the equipment except to say it was powerful and could even "mitigate" the drones, though he added that's not currently legal on U.S. soil.

READ MORE: Schumer calls on U.S. agencies to use advanced technology to identify mysterious drones

The state tallied 12 sightings Saturday and just one on Sunday.

Murphy urged Congress to give states more authority to deal with the drones.

The growing anxiety among some residents is not lost on the Biden administration, which has faced criticism from Trump for not dealing with the matter more aggressively.

In a call with reporters Saturday that was organized by the White House, senior officials from the FBI, Pentagon, Federal Aviation Administration and other agencies sought to reassure the public that the drones are not a national security or public safety threat, or the handywork of a malicious foreign actor.

The White House has said a review of the reported drone sightings shows many of them are manned aircraft being flown lawfully, echoing the opinions of officials and drone experts.

The Department of Homeland Security and FBI said they have no evidence that the aircraft pose "a national security or public safety threat or have a foreign nexus."

Speculation has nevertheless raged online, with some expressing concerns that the drones could be part of a nefarious plot by foreign agents.

Officials stress that ongoing investigations have found no evidence to support such concerns, but U.S. Rep Chris Smith, a Republican, on Saturday echoed such speculation.

"The elusive maneuvering of these drones suggests a major military power sophistication that begs the question whether they have been deployed to test our defense capabilities — or worse — by violent dictatorships, perhaps maybe Russia, or China, or Iran, or North Korea," he said.

On Monday, Pentagon spokesperson Maj. Gen. Pat Ryder cast doubt on the idea that the drones are engaged in intelligence gathering, given how loud and bright they are. He said about 1 million drones are registered drones in the U.S. and about 8,000 flying on any given day.

Pentagon spokeswoman Sabrina Singh has said the aircraft are not U.S. military drones.

In Boston, city police arrested two men accused of operating a drone "dangerously close" to Logan Airport on Saturday night.

READ MORE: Drone sightings lead to airspace shutdown at Ohio Air Force base, arrests near Boston airport