-Messenger photo by Chad Thompson Volunteer firefighters shoot stream of water into the rubble after a major fire erupted at Sinclair outside of Rockwell City Tuesday morning. The driver of the semitrailer truck was treated for smoke inhalation. No other injuries were reported.

UPDATE:

ROCKWELL CITY – A major fire ignited at Sinclair off U.S. Highway 20 Tuesday morning, destroying a semitrailer truck and the gas station building in its path.

The fire started at a semitrailer truck parked near one of the pumps, according to Rockwell City Fire Chief Shane Voith.

The driver got out of the truck after hearing or seeing something at the back of the truck, Voith said. At that point a fire started.

The driver was later treated for smoke inhalation, but didn’t suffer any major injuries, Voith reported. The driver was transported to Pocahontas Community Hospital.

The fire was reported at about 10:35 a.m.

“We could see a huge plume of black smoke from Rockwell City,” said Voith. The gas station, 2325 Marshall Ave., is located north of Rockwell city near U.S. Highway 20 and Iowa Highway 4.

Customers and employees were able to get a safe distance away from the fire before it completely engulfed the building. No other injuries have been reported.

Voith said a cause will not be determined.

“It’s (semi) burned to the ground,” Voith said.

The roof of the mains structure caved in. All that’s left is rubble.

Over $5 million in damage is estimated, according to Voith.

An investigator from the Iowa State Fire Marshal’s Office was on scene.

Firefighters from Rockwell City, Manson, Jolley, Lytton, Pomeroy and Knoke, responded. Calhoun County EMS, Pocahontas Community Hospital Ambulance, Rockwell City Police Department, Motor Vehicle Enforcement and Iowa State Patrol, were also on scene.