WATERFORD — The rumbling started early on the Fourth of July in western Maine, but fireworks weren’t to blame.

There was a Magnitude 2.1 earthquake centered near Waterford in Oxford County early Saturday, according to the U.S. Geological Survey.

Earthquakes of this magnitude aren’t uncommon in Maine. In February, a magnitude 2.2 earthquake occurred near Sabattus, the USGS said.

Comments are not available on this story.