A theft at a St. Louis-area hotel has police concerned — the thief got away with a Bushmaster AR-15 rifle and 100 rounds of ammunition.

The St. Louis Post-Dispatch (http://bit.ly/Xb9AzL ) reports that the items were stolen Monday from the backseat floorboard of an SUV parked at a Drury Inn in Maryland Heights. Police say the weapon was lawfully owned by a man from out of town who had been in the hotel a few hours when he discovered his vehicle had been broken into.

The SUV was locked but the weapon was in plain view. Police say leaving firearms unattended in a vehicle is not a good idea.

No other cars on the lot were victimized.