New Jersey drone sightings now prompt calls for state of emergency

A New Jersey state senator is calling for a limited state of emergency over the mysterious drones that have been seen flying over New Jersey in recent weeks.

"The State of New Jersey should issue a limited state of emergency banning all drones until the public receives an explanation regarding these multiple sightings," Republican state Sen. Jon Bramnick said in a statement Tuesday.

The call came amid numerous recent drone sightings reported across New Jersey in recent weeks. The drones are larger than the type typically used by hobbyists, officials and eyewitnesses have said.

The source and reason for the drones remains unknown as local, state and federal investigators look into the matter.

The Picatinny Arsenal in New Jersey -- a military research and production facility in Morris County -- has reported 11 confirmed sightings by a police officer or security guard in response to a report since Nov. 13.

"While the source and cause of these aircraft operating in our area remain unknown, we can confirm that they are not the result of any Picatinny Arsenal-related activities," Picatinny Arsenal Garrison Commander. Lt. Col. Craig Bonham II said in a statement Tuesday.

An FBI spokesperson said the agency is "doing all we can figure out what's going on.""The public can continue to call our 800 line, or submit a tip online, we are acting on every substantive lead that we get," the spokesperson said.

Law enforcement has limited authority to actually address such drone activity and the authority they do have is reactive rather than proactive, a senior U.S. official told ABC News.

The mayors of 21 towns in New Jersey penned a letter to Gov. Phil Murphy demanding action over the mysterious drones.

Michael Melham, the mayor of Belleville, New Jersey, posted Monday night on Facebook that there will be a briefing held exclusively for New Jersey mayors on Wednesday with the New Jersey State Police and the New Jersey Office of Homeland Security and Preparedness regarding the drones.

The drones have raised concerns due to their proximity to both a military installation and President-elect Donald Trump's Bedminster golf course.

ABC News' Alex Faul and Julia Reinstein contributed to this report.