9 firefighters were injured in the blast that devastated three businesses in the Greenwood neighborhood of Seattle Wednesday morning.

Officials have determined the blast was accidental, and are now trying to figure out where the specific leak was that led to the massive explosion.

Three business buildings were destroyed and officials say at least 36 others suffered damage, mostly from having windows blown out. They say it was an accident, and plan to place additional police patrols during the night for security to prevent any looting.

The neighborhood is still closed off for the investigation and cleanup. The blast occurred around 1:43am. Officials say there was a report of a gas leak in the area 39 minutes earlier.

Witnesses said it reminded them of the 2001 earthquake that shook buildings all over the city. One neighbor said they looked out their window and the "neighborhood exploded" according to NW Cable News.