Investigators are trying to determine what caused a fire Thursday morning at a gas line near a major highway interchange in south Minneapolis.
Eyewitnesses described an explosion, followed by a natural-gas fueled fire that shot flames high into the air.
Firefighters extinguished the fire, which happened on 60th Street near the intersection of Nicollet Avenue in front of a Cub Foods store. The street was still closed as investigators inspected the gaping hole that looked to be caused by a blast.
Authorities also checked for gas leaks in the surrounding area as they looked for clues on a cause.
The fire was so hot it melted part of the store's marquee, as well as the tires and headlights of cars in the store's parking lot. There were no reported injuries.
It also forced authorities to shut down Interstate 35W in both directions for a time. Highway 62 was also affected, along with several local streets. I-35W was back open, though the 60th Street ramp from southbound I-35W remained closed.
"A BALL OF FIRE"
Minneapolis fire crews arrived at the scene at about 8:40 a.m. Natural gas was fueling the billowing blaze, and crews first had to let it burn.
"A ball of fire was emitting from it, and we don't want to do anything in those situations, because we just want it to vent," Minneapolis Assistant Fire Chief Cherie Penn said. "We want it to burn off. It's better for it to burn off than to shut it down and have a problem."
CenterPoint Energy said the gas leak and fire occurred on a 20-inch steel natural gas line that was installed in 1994 to serve the greater Minneapolis area.
Despite eyewitness accounts of an explosion, CenterPoint spokeswoman Becca Virden said it was too early to determine what caused the fire. CenterPoint was not yet calling it an explosion.
"We'll know more as the investigation continues," Virden said. "The most important thing for the residents to know is that the safety of them and their property is our top priority."
Department of Public Safety spokeswoman Kristine Chapin said pipeline safety investigators were on scene.
Investigators were looking for clues inside the large hole in the street near the entrance to the Cub Foods parking lot on 60th Street.
Besides the traffic disruption, MnDOT officials were concerned the fire had damaged the 60th Street bridge. But inspectors later determined there was no damage, spokesman Todd Kramascz said.
EVACUATED AREA NOW OPEN
The Cub Foods was evacuated, as well as an apartment building, a Perkins restaurant, a school, church and some homes. Most people were allowed back in a few hours later, and Cub Foods reopened Thursday afternoon.
Eyewitnesses reported hearing an explosion before the fire, which could be felt from two blocks away.
Minneapolis resident Olivia Herstein, who lives about eight blocks from the scene and has covered fires as a newspaper reporter, said it was the biggest she had ever seen. She described it as a "column of smoke and fire."
Brad Solem, who works at Bobby and Steve's AutoWorld two blocks away from the scene, said he heard an explosion.
"The flames shot two or three times higher than the Cub Foods," Solem said. "You instantly could feel the heat two blocks away. It wasn't a huge, loud explosion, it was more of a boom-boom."
Mitch Madsen, of Minnetonka, was on his way into Cub Foods when he heard an explosion and saw the flames. He tried to get back into his car to fetch his cell phone, but the heat was too intense.
"I just headed into the store," Madsen said. "As soon as I got into the store I could see the big ball of flames."
Madsen's Mercury Mountaineer was one of several cars that were damaged.
"I think it's drivable, but the mirrors are melted, the roof rack's melted, the bumper's melted, the back window's blown out, I can't get the door open -- the key pad's melted," Madsen said.
The fire is the latest involving natural gas in the Twin Cities in recent years.
Last year a natural gas explosion leveled a home in St. Paul when workers disturbed a gas line that crossed a sewer line. The incident prompted a lawsuit and an inspection of thousands of such lines in the east metro.
State regulators ordered Xcel Energy to fix any additional crossed gas lines or face penalties.
Xcel spokesman Steve Roalstad said Xcel so far has inspected more than 25,000 lines and repaired 57. The project is expected to take about three years.
(Dunbar reported from St. Paul.)