A 500-pound chunk of ice that had built up at the top of a van was blown off, crushing the roof and windshield of a passing car.
The car driver suffered minor injuries but kept control of the car and pulled into a parking lot.
The van driver stopped, but drove off without checking on the man. Police on Wednesday were searching for the van's driver.
The accident happened Dec. 19, as Andy Burnett was driving his 1999 Ford Contour to work on a two-lane road near this southeast Missouri town.
"I saw the piece of ice start to come up off the van and head my way," Burnett said. "I had about a split-second reaction time and thought, "This is going to hurt.' "
The impact knocked his rear-view mirror into the back seat, and the front edge of the roof ended up about 6 inches from his head.