Investigators are sifting through the remains of the house at 5000 Arden Avenue in Edina that exploded Tuesday afternoon, looking for clues about what happened after workers struck a gas line.
Officials evacuated a large swath of homes in the area and blocked off busy neighborhood streets for hours after the accident Tuesday.
So far, the explosion does not appear to be an exact repeat of a recent situation in St. Paul, when a plumber was trying to clear a clogged sewer pipe and poked a hole in a natural gas line that crossed through the sewer connection.
But there are similarities.
At around noon yesterday, some unidentified contractors working in Edina were doing something called directional boring--drilling underground in a horizontal line. It's a way to install utility lines without the disruption of digging trenches.
But several blocks away the drill struck a gas line, at the intersection of 50th and Arden.
The crew alerted authorities. Police, fire and Center Point Energy workers arrived on the scene. The Center Point workers couldn't get to all the valves to shut off the flow of natural gas, so the line kept leaking.
Edina Fire Chief Marty Scheerer and his firefighters started moving people out of the area in case the gas exploded.
"We were in the process of evacuating the homes in the area," he said. "We literally had crews right next door when the explosion occurred."
That was about two hours after the contractors called and police arrived at the scene. Neighbors felt the explosion blocks away. Carl Granberg is director of the Edina Country Club, which is down the street from the house.
"We heard the explosion - we heard the 'boom' was what it was - and felt the building shake," Granberg said.
Several hours later, people living in the home were taking refuge in the club, but declined to speak to reporters.
Two people sustained minor injuries from the blast -- Center Point workers who were underground, trying to deal with the leak when the house exploded. They were wearing protective gear but the explosion still left them with 'flash-burns.'
CenterPoint spokeswoman Rebecca Virden said their injuries weren't serious.
"They were treated on the scene and continued to work," she said.
Before the explosion, fire fighters had knocked on the door of the house several times while evacuating the area. Fire Chief Scheerer said there was no one home when it exploded.
After the blast, fire crews decided to let the house to burn for hours as Center Point workers struggled to shut off the flow of gas to the damaged line.
Meanwhile, rush hour traffic ground to a halt as drivers encountered roads that police had abruptly blocked off.
At the end of the day, Edina Fire Chief Scheerer was still unsure exactly how the explosion occurred.
"Gas somehow migrated into the house," he mused. "It could've been a sewer line - mostly likely the cause."
That's what investigators will be trying to figure out.