Last Friday, a natural gas pipeline exploded in Westmoreland County, just east of Pittsburgh. One man was hospitalized after his house went up in flames, while other nearby homes were damaged and residents were evacuated.
This week, armed security guards blocked off the site of the explosion, as federal pipeline investigators worked with the owner of the pipeline and state officials to determine the cause of the blast.
The underground pipeline, which is owned by Spectra Energy, carries natural gas from the Gulf Coast to the northeastern U.S. It was built in 1981.