When their homes started to shake, residents of Rockaway Borough, New Jersey first thought there may have been an explosion Sunday at a nearby military base.

The U.S. Geological Survey said otherwise. They reported a 2.1 magnitude earthquake struck at 11:54 a.m. local time. Residents said the quake lasted about three seconds.

“I hope that’s it,” resident Bonnie Hook said. “It was a little scary. We’re not used to that in this area.”

Earthquakes in New Jersey are very rare but the Rockaway region has been shaken several times in the last year. On July 19th and 20th, 2012, at least four minor quakes shook the region according to seismologists.

Sunday’s quake was reported to be only 1.2 miles below the surface.