State regulators ordered a gas drilling company to halt operations today after four minor earthquakes shook an area 20 miles south east of Youngstown. No damage was reported. The Ohio Department of Natural Resources says the move is a precaution. The quakes ranged from 2.2 to 3.0 on the Richter scale. An injection well used to hold fracking wastewater has been tied in recent years to a series of earthquakes in the Youngstown area.