A deadly explosion in a fifth-floor Vancouver apartment has killed a woman in her twenties and left another man in hospital with serious injuries.

The cause of the blast had yet to be determined Saturday afternoon as homicide detectives were investigating the scene.

However, police are treating the incident as "suspicious."

The blast occurred around 8 a.m. Saturday morning at a building in the 3400 block of Crawley Street. Officers hope more potential witnesses will come forward.

CTV's Lisa Rossington said the relationship between the deceased woman and the injured man has yet to be established.

"They're not even calling it a homicide, even though homicide investigators are on the scene," she said.

Rossington said emergency crews, who responded to a call just after 8 a.m., arrived at the building to find an injured man sitting on the pavement.

"He was burned and he had glass shards impaled in him. This is what witnesses have told us," said Rossington, who added that several people spotted someone running away from the building just after the explosion.

Still, no link has been made between the blast and the person seen fleeing the area.

"Police are still trying to make the connection," said Rossington.

Officers said that there were no indications that the apartment was being used as a drug lab, The Canadian Press reported.