PORT COLBORNE, Ont. -- Emergency crews investigating a deadly house fire that killed a mother, her two children and her grandmother in southern Ontario have found a body in the charred rubble.

Niagara Regional police Const. Phil Gavin says a body was located on the second floor but has not yet been removed from the Port Colborne, Ont. home, nor has it been identified.

He says recovery efforts have been hampered by ice buildup in the home and crews are waiting to receive specialized equipment to thaw the material.

Two men, who police identified as family members, were able to escape the fire that broke out early Wednesday. One of them was the children's father.

Police have not named the victims, but friends and family identified them as Tammy Burd, 37, her children Samantha Zuvic, 15 and Joshua Zuvic, 2, and her grandmother, eighty-three-year-old Eva Burd.

The deaths have shaken the community and left neighbours grappling with grief.