EDMOND — A group of Edmond residents filed a lawsuit Monday against a dozen energy companies, claiming their saltwater disposal wells were in part to blame for earthquakes that hit central Oklahoma in recent weeks.

The lawsuit, filed in Oklahoma County District Court, said the companies acted negligently and their use of disposal wells constituted an "ultrahazardous activity." The nine homeowners said disposal wells operated by the companies "caused or contributed" to earthquakes.

Earthquakes of magnitudes 4.3 and 4.2 shook the Edmond area Dec. 29 and Jan. 1. No injuries were reported, although some residents and businesses reported items falling off shelves or walls. The quakes caused an hour-long power outage for several thousand residents when vibrations shook a substation, triggering a breaker.

Among the dozen energy companies named in the lawsuit are affiliates of Devon Energy Corp., New Dominion LLC, Marjo Operating Co. Inc. and Pedestal Oil Co. Inc.