WISCONSIN RAPIDS, Wis. — A central Wisconsin sheriff's deputy who lost an AR-15 rifle faces a brief suspension.

Wood County sheriff's Chief Deputy Randal Dorhorst tells WSAW-TV (http://bit.ly/1ctMgSm ) the deputy will serve a 12-hour suspension effective immediately. The deputy then will be reinstated following the suspension.

The deputy was putting the rifle back into his squad car when he inadvertently left it on the trunk of the car and drove off.

A passer-by discovered the rifle just outside of Wisconsin Rapids on the side of State Highway 34 and returned it to the sheriff's department Thursday.