A mother and her four children are dead after what appears to be a deliberately set fire tore through their townhouse in East Vancouver early Monday morning.
Officials said the victims were all members of the same family, with the youngest victim only eight years old.
The 38-year-old father is in hospital, suffering from severe burns.
Investigators suspect some sort of flammable liquid was used as an accelerant, said Vancouver Fire Department spokesman, Capt. Rob Jones-Cook.
Witnesses reported hearing an explosion as the fire tore through the townhouse in the 2400-block of Cassiar Street just before 4 a.m. PDT, Jones-Cook said.
He also said the fire appeared to have started at the back of the unit.
Dogs called in on 'major crime scene'
Police dogs have been brought in to help officers investigate what Jones-Cook described as a "major crime scene."
He said the fire did "very extensive damage" to the townhouse, with firefighters on the roof at one point to battle the flames.
Social services workers have been called in to help relocate people in adjoining units.
Classes have also been cancelled for 400 students at Thunderbird Elementary School, a block away from the fatal blaze.
Police have blocked off East Broadway Avenue between Boundary Road and Rupert Street, as the investigation continues.