A natural gas transmission line and a distribution line have been taken out of service in northwest Pennsylvania as state regulators continue to probe what caused an explosion that injured one person and destroyed a home, garage and greenhouse on May 28.

The Pennsylvania Public Utility Commission (PUC) said it has identified three pipelines located near the site of the incident in Redbank Township, about 70 miles northeast of Pittsburgh. Two transmission lines in the area are operated by TC Energy Corp. One small low-pressure line has been shut down as part of the investigation. The other pipe is an interstate line that was not impacted and is under the jurisdiction of the Pipeline and Hazardous Materials Safety Administration, PUC said.

The third line was supplying the house with natural gas and is operated by Empire Energy E&P LLC, a subsidiary of Australia-based Empire Energy Group Ltd., which has conventional oil and gas assets in Appalachia and the Midcontinent region.

According to local news media reports, first responders believe the explosion occurred in the basement of the home. The PUC, which is coordinating with the state Department of Environmental Protection (DEP) and other authorities, said it is trying to determine if natural gas service to the home was involved in the incident.

Empire Energy has 6,500 acres in three Pennsylvania counties, including in Clarion, where the blast occurred. It has 43 drilling permits in the county, including 29 that have been issued in Redbank, according to DEP data. It’s unclear if any of the company’s wells are located near the damaged property.

TC Energy spokesperson Carol Wirth said the company has personnel on site evaluating its lines in the vicinity of the incident. But she stressed that the cause of the blast is not yet known.