PUEBLO, Colo. -- No criminal charges will be filed in a natural gas leak and explosion that destroyed a Pueblo restaurant and a shop, killing one person and injuring seven.

District Attorney Bill Thiebeaut reviewed the findings from several federal agencies and the fire department to verify the blast was accidental.

The Nov. 13, 2008, explosion and fire, at Union Avenue and C Street, killed Ashley Johnson, 22. A survivor who was pulled from the rubble later died of cancer.

Federal investigators concluded in December the explosion was accidental.

They determined that natural gas leaked from near a gas main and structural flaws allowed natural gas to seep through the soil and into the basement of the Branch Inn, where it ignited. Johnson was shopping in A Classic Boutique next to the restaurant.

The Federal Bureau of Alcohol, Tobacco, Firearms and Explosives National Response team assisted local agencies in the investigation.

"Our office reviewed everything and concluded that their findings were accurate. It was an accident. We didn't take any further action," Thiebeaut said.

ATF investigators were unable to pinpoint the exact origin of the blast because the restaurant had numerous appliances, freezers, compressors and pilot lights that could have ignited the gas.

"It's hard to pinpoint which, except it was likely initiated in the basement," Pueblo Fire Inspector Woody Percival previously said. "There's a huge likelihood it was a compressor attached to a cooler in the basement."

Witnesses and victims said they smelled a sewage-like odor before the explosion, which investigators said could have been natural gas.

Natural gas is given an additive odor that can smell like sulfur or rotten eggs.