A sheriff in the heart of Tornado Alley says someone has been using work-release inmates to steal copper wire from Oklahoma City-area warning sirens.

Sheriff John Whetsel says he'll announce an arrest Thursday afternoon.

The U.S. Storm Prediction Center says Oklahoma City has been hit by more tornadoes than any other city in the country. Several storms have hit the area in the last month, dropping records amounts of rainfall that triggered widespread flooding. Tornados also were reported.

The sheriff didn't immediately provide details, saying only that he would hold a news conference to discuss the arrest of someone "who had Oklahoma Department of Corrections work-release inmates steal copper from Oklahoma County tornado sirens."

It's common in Oklahoma for local governments to use prisoners as laborers on certain projects.