ATF officials announced in a news conference Thursday the Branch Inn explosion that killed one woman and injured several others was caused by natural gas.

On Thursday, November 13 around 2 p.m. an explosion on the roof of the Branch Inn on Union Street in Pueblo completely leveled the two story restaurant. The force of the explosion also caused the roof of a neighboring boutique to collapse.

ATF officials say a build-up of natural gas in the basement of the Inn was accidentially ignited.

A final ruling on the cause comes as a relief to the family of co-owner and injured victim Frank Vigil. They say the nasty rumors of a meth lab, and criminal activity can now be laid to rest.

Officials say after a week of investigating, they can say the explosion was accidental and there was no criminal action.

Two women, Ashley Johnson and Jennifer Flower, were trapped beneath the rubble. Rescue crews pulled both women out within a short time. Johnson died at the hospital a short time later due to her injuries sustained.

Flower was airlifted to Denver Health Medical Center, where after a week of recovery she is in good condition.

Several other victims were hurt in the explosion as well.

After being trapped for more than four hours Eugene Roney, 74, was pulled from deep within the rubble by rescue crews. He was taken to Parkview Medical Center where he is listed in critical condition Friday. Rescue crews say Roney was believed to be inside the Branch Inn when it exploded and it is a miracle he is alive.

Vigil remains at Parkview in fair condition.

Three other victims were treated at a hospital and released. One person remains at St. Mary Corwin Medical Center. Their names have not been released.

Natural gas has a rotten-egg smell. Officials warn that if there is ever a strong rotten-egg smell it could mean danger and officials should be notified.

KKTV will have more on the findings of the ATF investigation. Stay with 11 News for the latest.

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