NEW CASTLE, Pa. (AP) — The state Department of Environmental Protection is investigating whether fracking contributed to two small earthquakes near a western Pennsylvania drilling operation.

DEP spokeswoman Melanie Williams says Hilcorp Energy Co. stopped fracking at the Mahoning Township site at about noon Monday. That was about 12 hours after the U.S. Geological Survey recorded a magnitude-1.9 earthquake and about 10 hours before another quake of the same size was recorded.

READ MORE: TSA Confiscates Loaded Handgun From Man At Philadelphia International Airport

A woman who answered the company’s phone in New Castle on Thursday referred The Associated Press to a spokesman at the company’s Houston headquarters who wasn’t immediately available.

READ MORE: 16-Year-Old Shot 8 Times In Deadly North Philadelphia Shooting Identified As Kanye Davis, Police Say

Williams says Hilcorp was fracking two wells on a four-well pad about 45 miles northwest of Pittsburgh when the first quake occurred.

There were no reports of property damage.

MORE NEWS: Temple University Student Samuel Sean Collington Killed In Off-Campus Shooting In North Philadelphia

Copyright 2016 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.