The cause of a food truck explosion late Friday in Lakeville remains unknown, the truck's owner said Sunday.

"I gotta find out what happened," Marty Richie said. "I gotta."

The blast heavily damaged several homes in and around the 16500 block of Joplin Path, including that of Richie, owner of Motley Crews Heavy Metal Grill, and his partner, Lisa. The truck had been parked in their driveway. Now, Richie said, parts of it are in four neighboring lots. There were no injuries.

Lakeville fire marshal Brian Carstensen did not return a message left at his home Sunday.

Richie said the damage to his truck and house will be covered by insurance. He's not sure whether he'll get another truck, but he will continue with plans to open a brick-and-mortar restaurant in downtown Lakeville in early June.

"We're moving forward 100 percent," he said. "This is not going to put us down."

John C. Levy, president of the Minnesota Food Truck Association, said such incidents are "amazingly rare."

The last one he knew of was in Philadelphia last summer when the grills on a food truck ignited propane vapor leaking from an unused tank. Two people died in that blast.

Locally, food trucks are inspected every year by regulatory authorities from health departments to licensing and transportation, he said.

Levy didn't know and Richie wouldn't say when the Motley Crews truck was last inspected.

Richie said the truck runs year-round. The truck's calendar shows it was last at Steel Toe Brewing in St. Louis Park on Feb. 27 and had planned to be at 612 Brewing in Minneapolis on Saturday.

The flame-painted truck blaring heavy metal rock music often set up shop at 7th Street and Marquette Avenue in Minneapolis and near Mears Park in St. Paul. It offered steak and chicken Philly sandwiches, Hawaiian sandwiches, brats and hot dogs.

Levy said he didn't want to speculate on what caused the explosion but said "perfectly sealed tanks don't tend to explode. Assuming it was propane-related, it was not necessarily human error. I really don't know. All I can say is it's an exceedingly rare occurrence, thank god."

Explosions are typically caused by vapor, he said. Other causes could be multiple propane cylinders, hot fryer oil and grills, other compressed gases, high voltage electricity or something else entirely.

"Propane tanks when properly monitored and inspected are not dangerous at all," Levy said.

Pat Pheifer • 952-746-3284