TRENTON, N.J. — Officials say sonic booms heard and felt along the coast from New Jersey to Connecticut Thursday afternoon were caused by a military fighter jet conducting tests.
Around 1:30 p.m., 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.
A Navy spokeswoman confirms that an F-35C from Naval Air Station Patuxent River, Maryland, was conducting supersonic testing off the east coast.
The jet has a top speed of nearly 1,200 mph.
Residents reported hearing loud booms and feeling the ground and buildings shake. The booms were heard as far away as Connecticut.
Tweets and Facebook updates flooded newsfeeds, 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.
Some Twitter users reported feeling tremors in Long Island and Connecticut.
New Jersey State Police said at the time that they were investigating the reports.
Another department asked people to stop dialing 911 after people began tying up the emergency lines:
Navy spokeswoman Connie Hempel says supersonic test flights are conducted almost daily in the same area but that most sonic booms aren't felt on land.
She says certain atmospheric conditions can increase the chance of hearing the booms.
U.S. Geological Survey geophysicist Bruce Presgrave says nine booms were recorded over 90 minutes.