Grey County OPP, along with the Ontario Fire Marshal's Office, continue to investigate a farmhouse fire that has now turned fatal.

Crews were called to a home on Sideroad 115 in the Township of Georgian Bluffs, northwest of Owen Sound, early Wednesday morning.

A 33-year-old woman and two boys, ages five and 11, were taken to hospital and later released. A seven-year-old girl was airlifted to a Toronto hospital with serious injuries.

A deceased person was located inside the home following the fire.

Friends say the man killed was Chris Johnson, though that has not been confirmed by police.

Matthew Madsen says he hasn't heard from his friend since Tuesday, and it was his rented farmouse that was levelled and his children that were injured.

He says Johnson was his best friend and "He was a great dad, excellent father, loved to hang out with his kids and it's a tragedy what happened."

Police are expected to officially release the identity after a post mortem examination scheduled for Friday in London.

The cause of the fire and the death are still under investigation.