Updated

A veteran state trooper and a civilian were electrocuted while fixing a flat tire on an antique fire truck when the truck's ladder touched a high-voltage power line, police said.

The fire truck, from the Canadian Fallen Firefighters Foundation, was being returned to Canada from a parade near Syracuse when a tire went flat near the Ogdensburg-Prescott International Bridge, said Ogdensburg Police Chief Richard Polniak.

State Trooper Shawn Snow was under the truck fixing the tire while a Canadian man was extending the truck's ladder to distribute the weight away from the flat right rear tire. When the ladder hit the live wire, both men were killed instantly, police said.

"How it ended up touching the wires, whether a piece of equipment failed and it slipped and touched the wires, or whether the act of jacking it up higher on one side caused it to touch, we just don't know yet," Polniak said.

Snow, 47, was a 19-year state police veteran. Authorities were withholding the name of the Canadian man until his relatives could be notified.

"This type of accident is somewhat incomprehensible," said state police Maj. Richard C. Smith Jr. "It is a terrible day."