GEORGIAN BLUFFS, Ont. -- An elderly woman is dead after a house fire in the community of Georgian Bluffs on the outskirts of Owen Sound.

Grey County OPP and firefighters were called to the fire (on 30th St. W.) at about 5:30 p.m. Thursday in the lower level of the single family, split level home.

Witnesses believe it started after an explosion involving oxygen tanks, but officials have not yet confirmed the cause of the fire.

Police confirm one person is dead, and neighbours say it was an elderly woman.

A 23 year old man -- said to be the woman's grandson -- suffered life-threatening injuries after reportedly going back into the home to try to save his grandmother.

No one else was home at the time.

The Fire Marshal's office and the Technical Standards and Safety Authority are assisting with the investigation.