LITCHFIELD (AP) -- Authorities in Meeker County say someone left "booby traps" in a farmer's field apparently meant to damage farm equipment.

Sheriff Brian Cruze says a farmer near Cedar Mills on Monday reported minor damage to a combine after a chain was drawn into the machine during harvesting.

Cruze says it's premature to speculate on motive.

The sheriff says the chain may have been in the corn for weeks or months. But he says when the farm family got deeper into the crop, it happened again.

Mindy Johnson's family farms about 2,000 acres of corn and soybeans. She says the second incident involved a 6-foot piece of steel rebar pounded into the ground near a cornstalk where it was hard to see.

Johnson says she doesn't know why her family's farm would be singled out.