UPDATE, 5:30 p.m.: Sonic booms were likely caused by test flights out of Maryland.

As of Thursday afternoon, officials were continuing to investigate a series of tremors — first reported in south Jersey, and then much farther north.

The US Geological Survey has said they were sonic booms, not earthquakes — but as of 4:20 p.m. Thursday, no cause had been identified.

The following are accounts from New Jersey 101.5 listeners, calling into the station newsroom or the Deminski and Doyle Show, and from NJ1015.com readers.

Ken, Little Egg Harbor:

“My wife is panicking over here. We’ve had eight of them so far, one of them strong enough to knock the cable out. I mean the house is shaking like you were in a hurricane. I mean it’s just shaking all over the place and we’ve gone through eight of them and they’re coming out of the ground and what you first hear is a rumble off to the northwest, and then about three minutes later everything just starts shaking.”

He said if it has been a sonic boom you would’ve heard jets but “this shaking is in the air, it’s not in the ground.” He said he’s never actually felt a sonic boom before.

Did you feel the tremors? Tell us on Facebook or Tweet us @NJ1015.

Lauren, Manalapan:

“I was in the house hearing some strange noises and then I was walking my brand new puppy and sure enough I was in the earthquake a couple of years ago and felt in in Marlboro. But there was some shaking, I hear strange noises coming from the sky and it was just reminiscent of what I heard a few years ago.”

She said she often has aircraft flying over her house from the Joint Base and this didn’t sound like anything she had heard in the past.

Missy, Cape May County:

“We’ve had eight of these incidents. The first was at 1:21, then seven minutes later there was a second one and then there was a half hour gap and then after that we had just about every five minutes and the last one I felt was at 2:29. What we experienced here was the windows rattling … as if a very large truck was shaking everything. It seemed very different than what I experienced in the 2011 earthquake.”

She said what she felt then made it seem as though she was moving but this time, "it felt like everything else was shaking.”

Reed, Ventnor:

“I was up in Little Egg Harbor. ... I’ve heard sonic booms before. This was more of a ground shake.”

“It sounds like it’s something like an ice quake, you know when the ground’s frozen and it thaws rapidly it can cause these tremor-like vibrations in the ground.”

Diane, Barnegat:

“I thought it was a bad wind storm but there were no trees rustling. Then the glasses on the shelves started to shake."

— Reporting by Toniann Antonelli, Annette Petriccione, Louis C. Hochman and Dan Alexander

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