The United States Geological Survey says that a 4.0 magnitude aftershock struck in Hunterdon County several hours after an initial 4.8 magnitude earthquake occurred in the same area.

The aftershock hit around 6 p.m. Friday in Tewksbury. The initial earthquake occurred at 10:23 a.m. in Whitehouse Station. The impact of the earthquake and aftershock were felt in multiple states in the Northeast. The earthquake was the strongest recorded in the Northeast in more than a decade, according to the USGS.

There were not any reports of widespread damage. But the temblor severely damaged three multifamily homes in Newark, displacing nearly 30 residents.

LIVE UPDATES: Earthquake in New Jersey felt throughout tri-state area

Isolated, but not insignificant, Readington's mayor says the township found pieces of its 18th-century gristmill spread across the road.

"This mill specifically provided food for George Washington's troops, so it's a critical part of American history,” says Mayor Adam Mueller.

Mueller says the township recently received a grant to repair a portion of the mill. Now, they'll be looking for more funding to address the new damages.

"It survived this long. Nearly 250 years so far. We're hoping to keep it for another 250,” he says.

Earthquakes are less common on the eastern than western edges of the U.S. because the East Coast does not lie on a boundary of tectonic plates. The biggest eastern quakes usually occur along the Mid-Atlantic Ridge, which extends through Iceland and the Atlantic Ocean.

“I’ve lived here essentially all my life and I never had an earthquake before,” says Tewksbury resident Peter Greaves.

The earthquake caused some flight delays as area airports held flights at their origin for a time to make sure runways were not damaged. Traffic at the Holland Tunnel was also stopped for about 10 minutes for inspections.

President Joe Biden said he spoke to Gov. Phil Murphy about Friday's earthquake. The White House said the administration would provide help if needed. The Associated Press wire services contributed to this report.