Two Arlington residents were killed and two other people were critically injured Saturday night in a five-vehicle chain-reaction crash on State Highway 171, state authorities said.

Crash with tractor in Hill County What we know: Texas Department of Public Safety (DPS) troopers responded at approximately 8:30 p.m. to the multi-vehicle wreck near County Road 4223, north of Hillsboro.

According to investigators, a farm tractor towing equipment was traveling northbound with its lights flashing when a northbound Ford Fiesta passed a pickup truck, re-entered the right lane, and struck the farm equipment, causing it to detach into the road.