Two people were injured after a Kentucky natural-gas line exploded and sparked a blaze early Thursday morning, setting homes on fire and leaving a large crater, officials said.
Columbia Gulf Transmission LLC, which runs the pipeline that runs near the small town of Knifley, said the company detected a "drop in pressure" on the gas line at 1:05 a.m. Central time.
The two victims were treated and released from the hospital by 8 a.m., the company said in a statement, adding that the cause of the "rupture" was under investigation.
Adair County emergency director Greg Thomas told the Louisville Courier-Journal that the explosion destroyed three homes, two barns and as many as six vehicles. Twenty homes had to be evacuated, he told the newspaper.
"There is now a crater 60 feet deep and it blew rocks out, and I don't mean pebbles ... big rocks," Thomas said.
In its statement, Columbia Gulf Transmission identified the line as Line 200, adding that: "In general, this system has been safely operating since the mid-1950s and 1960s."
The same line reportedly suffered an explosion in Estill County in January 2012; no one was hurt in that incident, which happened roughly 90 miles northeast of Knifley.
"We have team members on site in Adair County, working closely with appropriate local, state and federal authorities to review all aspects of the incident, including factors such as the operating, inspection and maintenance history of the pipeline, environmental conditions at the time of the rupture, and outside activity that may have taken place in the area," the company said in a follow-up statement Thursday.