Glenshaw, PA- Officials say they smelled gas but have yet to pinpoint the exact cause of an explosion that badly damaged a vacant house in the Pittsburgh suburb of Shaler Township.

Allegheny County’s chief deputy fire marshal says a preliminary survey by Equitable Gas Co. showed no leaks at the home or in the area.

But Cherry City Volunteer Fire Department Chief Jim Skalos says firefighters smelled natural gas when they arrived at the Shaler Township house on Wednesday. The explosion occurred around 11:30 a.m.

Part of an exterior wall was blown out of the home and another part buckled.

The landlord says her last tenant moved out April 12. She plans to tear down the house after officials finish their investigation.