Police on Vancouver Island responded to a call on Christmas night to find two murdered children and an injured man inside an Oak Bay apartment.

Police initially said the deaths were suspicious, and early Tuesday evening the Vancouver Island Integrated Major Crime Unit confirmed it is investigating the incident as a double homicide.

"This is a devastating incident and we cannot begin to express our sympathy to all those touched by this tragedy," Cpl. Shane Rappel said in a release.

Police responded to the call just after 5 p.m. at an apartment building in Oak Bay, just east of Victoria, close to the marina at the corner of Beach Drive and Goodwin Street. The entire building was behind police tape on Christmas night as officers tried to figure out what happened.

Dept. Chief Ray Bernoties who was at the scene called it a "tragic set of circumstances."

Police are not seeking additional suspects and say the public is not at risk.

The children were aged four and six, police say. According to neighbours, they were two little girls and their father was transported to hospital.

Forensic investigators spent Boxing Day documenting the scene, carrying boxes of equipment and latex gloves.

Residents in the apartment building said they are shaken.

"It was shock," said Lorraine Jasmin. "There were two ambulances. There were five police cars and two fire trucks and we thought this was very odd."

The father and his kids were often seen together, said another neighbour.

"Dad and kids, they seemed happy," said Chris-Ann Lake. "The kids, I saw them the other day and they were playing and happy."

Police have not confirmed the cause of death.

With a report from CTV Vancouver's Nafeesa Karim