MARION TWP, Beaver County — A mobile home Thursday night was destroyed by fire near the Beaver-Butler County line, authorities said.

A Butler County firefighter had to be treated at a hospital after suffering a minor injury while battling the blaze.

The owners, an elderly couple whose names were not immediately known, were away when the fire broke out about 7:15 p.m. at their singlewide trailer on Route 68 behind Will’s Sport Shop.

A passing motorist saw the flames and called 911, initially believing the home was in Zelienople.

The trailer actually is in Beaver County, about 500 feet west of the Butler County line.

“We were first on scene and the home was fully involved when he got there,” said Chief Rob Reeb of the Zelienople Volunteer Fire Department.

The home sits about 300 feet from the road. Several tankers had to provide water to put out the fire.

Reeb said that moments before the fire a thunder-and-lightning storm hit the area but he did not know if that may have ignited the blaze.

A Zelienople firefighter twisted an ankle when he slipped in mud and had to be taken to UPMC Passavant Cranberry, where he was treated and released.

The local chapter of the American Red Cross was called to assist the owners, who did not have insurance on their home.

Along with the Zelienople VFD, assisting were fire departments from Big Knob, Daugherty Township and Economy in Beaver County and Cranberry Township and Harmony in Butler County.

The last crews were back at their stations about 10 p.m.