Calgarians expressed shock and sadness following the news that a stabbing near the University of Calgary had left five young adults dead.
Three males were found dead at a house in the northwest neighbourhood of Brentwood, according to police, and two more victims died later in hospital.
"The University of Calgary is mourning the loss of five young people killed early this morning in Brentwood. The identities of the deceased have not yet been confirmed by Calgary Police Services," said a statement on the U of C website.
"This is the worst mass murder in Calgary's history," said Calgary Police Chief Rick Hanson at a news conference Tuesday morning.
Many Calgarians took to Twitter to express their shock and disbelief at the events as they unfolded.
Mayor Naheed Nenshi also tweeted his condolences.
All five victims were in their late teens and early 20s, say police.
According to neighbours, U of C students were renting the house and were holding a Bermuda Shorts Day-themed house party.
Police have a suspect in custody.
Cheryl Rodger, who lives down the street but didn’t know the residents, told the Calgary Herald there had never been any problems associated with the house before.
“Five young kids are gone,” she said. “I feel sorry for their mothers, their fathers. Just terrible.”
Neighbour Doug Jones told the Calgary Sun between three and five university students lived in the home.
He said the residents were having a small, quiet party in their backyard Monday evening.
"Soon as it started cooling off and it started getting dark, they moved inside," he said.
"It was no different or no louder than when we get together for a barbecue."
Check out the slideshow below for more photos from the scene and reaction from Calgarians.