The cause of a fire that destroyed an aircraft at Sandy Lake Tuesday afternoon is still unknown.

No one was hurt when a Wasaya Airways Hawker-Siddley 748 caught fire on the ground and sent thick plumes of black smoke billowing into the sky.

The two-person crew had flown the plane from Pickle Lake with a cargo of fuel, transported in bladders. There were no passengers on the aircraft.

A news release from Wasaya's Thunder Bay office says the incident occurred "during ground operations" at the Sandy Lake airport.

Stan Roseborough, who works for Sandy Lake First Nation in community development services, said when he saw the black smoke he went to the airport right away and radioed for water trucks to help.

"It was quite a sight," he said. "There was explosions there. Tanks were blowing up inside the plane. It's too bad though. They're nice planes."

Roseborough said bystanders stayed far back because of the explosions and heat.

The Transportation Safety Board won't send a team to the scene because it considers the incident an industrial accident. However, Wasaya Airways is investigating and an environmental assessment is also underway.

Wasaya Airways provides passenger service to more than 25 destinations across northwestern Ontario, as well as chartered passenger and cargo service.