SAN FRANCISCO — A light earthquake has rattled the San Francisco Bay area and was felt during the Giants' game with the Pittsburgh Pirates tpnight.

Many felt the temblor — with a preliminary report as a 4.0-magnitude from the U.S. Geological Survey — at the Giants' waterfront ballpark. There was no interruption of the game. During the 1989 World Series here between the Giants and Oakland Athletics, a 6.9 earthquake during warmups before Game 3 and delayed the rest of the Series.

The quake hit just after 9 p.m. and could be felt throughout the region.

The temblor's epicenter was near Alamo, about 28 miles east of San Francisco.

Contra Costa County Sheriff's spokesman Jimmy Lee says there are no immediate reports of damage or injuries in Alamo or surrounding communities.