More mysterious drones spotted over New Jersey This is what we know.

For more than two weeks, New Jersey residents have reported seeing mysterious drones hovering over their homes and neighborhoods at night in the northern part of the state.

The drones, sometimes traveling in groups, have been spotted nightly in some areas. However, law enforcement authorities were unable to provide an explanation for the large number of sightings.

The FBI is taking the lead in the investigation and has asked for information from the public to determine whether the drones pose a threat to local residents.

MORE: The FBI is asking New Jersey residents to help solve the drone mystery

“Unfortunately, we don’t have many answers and we don’t want to speculate or hypothesize about what’s going on,” FBI spokeswoman Amy J. Thoreson said Wednesday. “We’re doing everything we can to find out.”

The drones interfered with a rescue helicopter picking up a patient and led to FAA drone flight restrictions over Trump National Golf Club in Somerset County and Picatinny Arsenal in Morris County.

Here’s what we know so far about the drone sighting:

When did nighttime drone sightings begin?

On November 18, police began investigating reports of a large number of drones hovering in Morris County at night.

Where have unexplained drones been reported?

Reports of drones have been filed with police in Mendham Borough, Mendham Township, Morristown, Morris Township, Chester, Randolph, Rockaway, Morris Plains, Dover and Parsippany in Morris County. Authorities in Hillsborough and Branchburg in Somerset County and communities in Warren County have also received reports.

There have been numerous reports on social media of sightings in other cities, including numerous reports in Hunterdon, Monmouth and Sussex counties.

The Warren County Prosecutor’s Office issued a statement Wednesday acknowledging that “recent drone activity has been observed in Warren County.” Prosecutors asked residents to help document drone sightings, “particularly those involving critical infrastructure.”

There have been reports of sightings near Merrill Creek Reservoir in Harmony, Warren County.

The FBI also said there had been sightings in “several areas along the Raritan River.”

What is unusual about the sightings?

Residents said the drones appear in large numbers and appear to hover in the same area night after night. According to the reports, some of the drones were also unusually large.

A Morris County resident reported seeing eight drones at once near Black River Middle School in Chester. Another reported seeing 15 people in Morris County in three hours.

Some of the drones were described as appearing to be the size of a car or small airplane.

How are the authorities reacting to the reports?

The FBI confirmed last week that it was investigating the sightings.

On Monday, the FAA announced it had temporarily banned drones from the airspace over Picatinny Arsenal in Morris County and Trump National Golf Club in Bedminster. The FBI said it requested the restrictions “out of an abundance of caution.”

The FBI asked the public for tips on sightings on Tuesday to determine whether the drones pose a danger to the public.

Local police officials said the drones pose no threat to residents.

What should residents do if they spot a suspicious drone?

The FBI urged the public to report sightings via the hotline 1-800-CALL-FBI (800 225-5324). Officials also asked for photos and videos of the drones to be uploaded to Tips.fbi.gov. For online reports, click “Submit a Tip” and then use the “Other FBI Crimes” tab.

What are possible explanations for the sightings?

It remains unclear whether the large number of drone sightings is related – or whether there is a single explanation for all the devices spotted over New Jersey.

Some people suspected that the drones were being used by criminals to investigate houses for robberies. Others suggested this was the case be used by possible terrorists. Police officials have not said whether any of those theories are plausible.

Theories abound on social media that the drones belong to hostile foreign powers, are used for political intrigue, or are controlled by aliens.

Pramod Abichandani, professor and director of the Advanced Air Mobility Lab at the New Jersey Institute of Technology in Newark, doesn’t believe these theories.

“To me,” he said, “the simplest explanation is the right explanation.”

He believes the drones likely belong to commercial or U.S. military operators. Whatever company owns the drones would likely have significant money and manpower to fly that many drones for many hours for many days, he said.

This is particularly true when drones fly in groups, so-called swarms, which is technically demanding.

“There are companies in New Jersey that are defense contractors and operate drone swarms,” said Abichandani, who teaches a “Fundamentals of Drone Science” course at NJIT. “There are now enough smart people in the world, in the United States and in New Jersey, who, if they really want to, can start experimenting with drone swarms.”

If the drones were monitoring homes for future crimes, as some suspect, or being used by hostile foreign forces, they probably wouldn’t be as loud or brightly lit, he said.

“It would be extremely negligent on the part of people working for foreign powers to simply expose themselves like that,” Abichandani said. “It takes an incredible amount of skill to do something nefarious with drones.”

Is it legal to fly a drone at night?

The law is complicated and depends on several factors, including: how much the drone weighs, whether the pilot has an exemption from the FAA, whether drones are used for commercial purposes, whether the operators have passed a required test, and whether the drone has one has flying over people. Night flying drones must have a range of up to three miles.

What penalties do drone operators face?

Operators who endanger aircraft or pedestrians could be fined up to $75,000 and lose their drone operators’ pilot licenses.

For example, drones over a landing zone prevented a rescue helicopter from picking up an accident victim last week near Raritan Valley Community College in Somerset County, local officials said. It is unclear who was piloting the drones. The drone operator could face fines or loss of their drone pilot certificate if cited by law enforcement.

How can you tell if you see a drone and not a helicopter?

Drones typically have four propellers in a square formation, each with one light — two green and two red, Abichandani said. Helicopters typically have one light on the tail rotor and one in the front. Both can be quite loud.

Do drones have registration numbers that allow for easy identification?

The FAA has required a “digital license plate” for drones since March. The agency is developing data sharing capabilities for law enforcement agencies to access FAA registration information, an FAA spokesman said Wednesday.

While newer, store-bought drones have a feature that broadcasts their identification information, many people have older drones or build their own from parts that don’t have identification.

“You can’t fly a drone without having a remote ID broadcast service on the drone,” Abichandani said. “But how many people actually follow it is another question.”

Can people shoot down drones?

Shooting down a drone is a federal crime and can be dangerous to people in the area, drone experts say.

Can drones be detected?

There are ways to disable a drone by either jamming its radio signals or tracking it with another drone and dropping a net over it, Abichandani said.

But the FCC regulates radio frequencies, and frequency jammers are illegal for most people, said William Austin, president of Warren County Community College and the founder of his associate’s degree related to drones.

It could be dangerous and possibly illegal to intercept drones. It could also be dangerous for people on the ground.

“This sounds like a great idea, but to get it on the ground you need someone who is very familiar with the equipment,” Austin said.

FBI officials did not respond to questions about whether law enforcement officers have tried to capture drones that appear to hover over the same areas in New Jersey every night.

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Tina Kelley can be reached at [email protected].