NEW JERSEY – Around 1:30 p.m. Thursday, tremors shook south New Jersey and other parts of the East Coast, briefly sending residents into a panic.

The shaking was so strong that some called 911 while many others took to social media to report the phenomenon.

Tweets and Facebook updates flooded in, but experts from the United States Geological Survey initially couldn't explain the shaking and had no evidence of an earthquake. USGS officials finally identified the cause of the 'tremors' as a sonic boom near Hammonton, N.J.

RELATED: WHAT IS A SONIC BOOM?

Soooo I'm in Manahawkin #NewJersey and that's the 5th tremor in the last hour or so. #earthquake? First time I've ever felt that — Katie Ballinger (@KTStarks) January 28, 2016

That's 6 times and they seem to be getting stronger each time. #new jersey #earthquake? #sonicboom — Rob Kelly (@robkellysurf) January 28, 2016

Some Twitter users are even reporting tremors in Long Island and Connecticut.

Anyone else on Long Island feel earthquake or am I just losing it? — Kevin DeLury (@kevindelury) January 28, 2016

House just shook for the 5th time here in CT, along Long Island sound. Very light, but enough to make a door rattle each time #earthquake — John Nash (@NikonNash) January 28, 2016

@QuakeAlarmMex feeling tremors here on Long Island as well at @2:12pm. — Laurie Henneborn (@HenneGeek) January 28, 2016

New Jersey State Police say that they are investigating the reports.

We are not reporting any type of seismic blasts anywhere in NJ. Looking to confirm reports of reported tremors. — NJSP - State Police (@NJSP) January 28, 2016

Another department asked people to stop dialing 911 after people began tying up the emergency lines:

@NJHTPD is aware of the shaking and tremors currently being felt in the area. Please DO NOT call 911 unless it's an emergency. — Twp of Hamilton PD (@NJHTPD) January 28, 2016

The USGS confirmed that the shaking was due to a sonic boom originating 3 kilometers northeast of Hammonton, New Jersey.

This is a developing story. Check back later.