An earthquake that hit southern Maine and was felt in New England states as far away as Connecticut caused no apparent damage or injuries, but rattled residents throughout the region.

The U.S. Geological Survey said the 4.0 magnitude quake struck around 7:12 p.m. on Oct. 16 and its epicenter, about 3 miles west of Hollis Center, Maine, was about 3 miles deep. That location is about 20 miles west of Portland.

"It was loudest bang you ever heard in your life. We actually thought it was an explosion of some type," said Jessica Hill, owner of Waterboro House of Pizza, about 10 miles away.

The Seabrook Station nuclear plant, about 63 miles away in New Hampshire, said it was not affected. The plant has been offline for refueling.