A series of sonic booms that rattled part of the Eastern seaboard Thursday afternoon -- felt from southern New Jersey to Long Island -- was likely caused by Naval aircraft testing in the area, the Navy said.
The Naval Test Wing Atlantic, based out of the Naval Air Station in Patuxent River, Md., was conducting routine flight testing in the Atlantic Test Ranges this afternoon "that included activities which may have resulted in sonic booms," the Navy said in a statement. Other military aircraft, including both the Navy and Air Force, frequently use the ranges for testing and training.
"The test wing is critical to the safe test and evaluation of all types of Navy and Marine Corps aircraft in service and in development," the Navy said.
A single-engine F-35C fighter jet from the Naval Air Station in Maryland was conducting supersonic testing in a cleared military flight area off the east coast earlier today, accompanied by an F/A-18 fighter jet, the military said.
Military aircraft routinely conduct supersonic flights offshore in an area called the Test Track, which parallels the entire coast of the Delmarva Peninsula near Delaware, Maryland and Virginia. Test aircraft from the naval air station executes supersonic flights almost daily, and most of the sonic booms are never heard on the ground, according to the Navy.
"As with all flight operations, the Navy takes precautions to lessen the impact of testing and training activities on the community," the military said in a statement.
Certain weather conditions increased potential to hear the sonic boom, according to the Navy.
Some initially believed that it was an earthquake.
Earthquake confirmed in Hammonton New Jersey. No injuries reported.— Ocean County Sheriff (@OceanCounty911) January 28, 2016
The boom was centered north of Hammontown, NJ, around 1:30 p.m. It was the first of nine booms reported in southern New Jersey and along the Eastern Seaboard to Long Island, New York in the hours following the initial boom, the USGS said.
The National Weather Service in Mount Holly said it contacted researchers at Columbia University who confirmed that the trembling was not an earthquake.
We contacted Lamont Doherty Observatory @ Columbia University who confirmed that it was not an earthquake & likely result of a sonic boom.— NWS Mount Holly (@NWS_MountHolly) January 28, 2016
A sonic boom is the thunder-like noise a person hears when an airplane, travels faster than the speed of sound. The boom travels through the air with the plane, so it arrives at different ground locations at different times, the USGS said.
Since many have asked: A sonic boom travels through the air w/ the airplane so it arrives at different ground locations at different times.— USGS (@USGS) January 28, 2016
A military facility in Trenton, the Joint Base McGuire–Dix–Lakehurst, said it doesn't house any aircraft capable of supersonic flights. The base also said it wasn't conducting any ground artillery training.
"It wasn't us," a spokesperson for the Joint Base McGuire–Dix–Lakehurst said.
The 177th Air National Guard, which flies F-16 jets, also they were not conducting any flights in the region.
The Federal Aviation Administration and the North American Aerospace Defense Command confirmed to ABC News that there were no planes – commercial or military – operating in the area that could have caused a sonic boom.