BOULDER, Colo. (AP) - Authorities say an elderly Boulder County man was found dead after he was run over by his tractor on his property, where he lives alone.

Isaac Drieth, 87, was found by his adult grandson on the property north of Longmont on Friday afternoon.

The man's family had dropped him off at home Thursday, and investigators believe he was run over Friday as he was standing beside the tractor while it was in gear.