Niagara Regional Police say one woman is dead and three others, including a woman and two children, are unaccounted for after a house fire Wednesday morning in Port Colborne, ON, Canada.

The fire was reported at 1:20 a.m. (EST) and once on scene, Port Colborne Fire and Emergency Services firefighters found the home, on Nickel St., engulfed in flames.

Also on scene, were regional police and Niagara EMS paramedics.

Police said it was reported that at least four people were inside the home, while at least one or more had escaped the blaze.

Firefighters were able to rescue an elderly woman from the home, and fire chief Tom Cartwright was seen performing CPR on her before an ambulance arrived and paramedics took over.

Police said the woman did not survive.

Firefighters were on scene until just after 6 a.m., and had called for mutual aid from Welland Fire and Emergency Services, which sent an aerial truck and a pumper with extra manpower.

Police said firefighters battled flames and hot spots throughout the early morning hours.

The residence sustained significant structural damage and has been deemed unsafe to enter.

Unaccounted for and believed to be still in the residence are a 37 year old female, 15 year old female and a 2 year old male.  Their identities are not being released.

Police are working with the fire service and Ontario Fire Marshal's office during the investigation.

The cause of the fire is unknown at this time as the investigation is in the early stages.