Cut gas line at center of NTSB investigation into deadly Ohio explosion

The National Transportation Safety Board said a cut to an inactive but still pressurized gas line will be a central focus of their investigation into what caused a devastating explosion that rocked downtown Youngstown, Ohio.

The blast occurred near Central Square on Tuesday afternoon and impacted a building that contains a Chase bank and apartments. One person was killed and seven others injured in the explosion, officials said.

The NTSB sent a team of pipeline and hazardous materials investigators to Youngstown on Wednesday to investigate the natural gas explosion.

MORE: NTSB investigating after deadly explosion rocks downtown Youngstown, Ohio

The preliminary investigation suggests that work crews were in the basement of the building to reportedly clear out old utility infrastructure prior to the explosion, according to NTSB board member Tom Chapman.

"A possible third-party cut to the pressurized service line is a central focus of our investigation to determine the cause of the gas release and subsequent explosion," Chapman told reporters during a press briefing Thursday.

Following the explosion, the Public Utilities Commission of Ohio and Enbridge Gas, the service provider for the area, gained access to the basement and discovered a cut to the pressurized but inactive below-ground service line, Chapman said.

Part of the investigation "will determine exactly why that apparently abandoned service line was still pressurized," Chapman said.

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Chapman said there is no evidence to suggest anything "nefarious" in the incident.

"Part of what we'll be looking at is what are the proper procedures and were those proper procedures followed," he said.

The NTSB’s investigation is expected to last approximately one week, with a preliminary report anticipated in about 30 days. Final reports typically take between 12 and 24 months to complete.

Chapman called the damage in the explosion "stunning."

"The damage to the building is devastating," he said.

The floor collapsed into the basement, which was flooded, officials said.

The body of a man who was an employee of the bank -- identified as Akil Drake -- was recovered from the basement early Wednesday morning, officials said.

The building and a neighboring hotel have closed and streets in the surrounding area are shut off to traffic indefinitely due to the potential for structural collapse, authorities said.

Cut gas line at center of NTSB investigation into deadly Ohio explosion originally appeared on abcnews.go.com