CONCORD, Ill.- Three people were injured, two of them seriously, in an apparent propane gas explosion Friday morning at a home in Concord, Ill., a small White County village south of Carmi.

Two contractors with Bowles Heating and Air Conditioning of Enfield, Ill., were working in a crawl space beneath the Milas and Ilene Littrell home in Concord when a propane furnace malfunctioned and exploded.

The contractors, identified as Greg O’Neal, 40, and David Howard, 56, both of Enfield, suffered burns, as did Milas Littrell.

“The workers had shut off the gas at the propane tank before starting their repair work,” said White County Sheriff Doug Maier. “Apparently there was a buildup of gas in the crawl space or some other leak that reached an ignition source, causing the blast.”

Maier said O’Neal appeared to be the most severely burned and was airlifted from the scene to the burn unit of St. John’s Hospital in St. Louis. A second helicopter transported Howard to Deaconess Hospital in Evansville.

Littrell was standing outside his home and was knocked to the ground by the explosion. He suffered relatively minor burns to his lower arms and was treated at the scene.

The Carmi Fire Department was dispatched to the explosion at 10:29 a.m. Friday. The fire had been extinguished before firefighters arrived.