Two people have died and four others remain in hospital after a building partially collapsed Friday in London, Ont.
Doctors at the London Health Sciences Centre said one individual died several hours after the collapse, having arrived at the hospital without vital signs.
Another person was trapped in the ensuing collapse, but police said late Friday evening that the person has died.
Of the injured, one is in critical condition, another is in serious condition and two others are in fair condition.
A statement from the City of London says the collapse happened at 555 Teeple Terrace in the city's west end just before noon when the wall of a four-storey building under construction suddenly gave way.
London Fire Department deputy chief Matt Hepditch also said it's not yet known what might have caused the collapse.
Local resident Elizabeth Rutherford said she heard a "horrendous crash" shortly after arriving home.
"I could hear all this yelling," she said. "I kept hearing them and thought there's something serious going on. I opened one of the curtains and all hell was breaking loose out here."
Rutherford said she saw construction workers rushing around and shortly after, emergency crews began to arrive.
Police are asking people to avoid the area. The roads leading to the site have been blocked to traffic.
The city has activated its emergency operations centre and, shortly after 1 p.m., Toronto Fire Services chief Matthew Pegg tweeted that a heavy urban search-and-rescue team has been authorized to be sent to London.
<a href="https://twitter.com/ONFireMarshal?ref_src=twsrc%5Etfw">@ONFireMarshal</a> <a href="https://twitter.com/jonpeggOFMEM?ref_src=twsrc%5Etfw">@jonpeggOFMEM</a> have authorized the deployment of the Heavy Urban Search and Rescue (HUSAR) team to London, Ont for a structural collapse. The team is preparing and deploying. <a href="https://twitter.com/Toronto_Fire?ref_src=twsrc%5Etfw">@Toronto_Fire</a> <a href="https://twitter.com/TorontoMedics?ref_src=twsrc%5Etfw">@TorontoMedics</a> <a href="https://twitter.com/TorontoPolice?ref_src=twsrc%5Etfw">@TorontoPolice</a>—@ChiefPeggTFS
In announcing the second death, police said late Friday that rescue efforts have shifted to recovery operations.
London's Victoria Hospital had also issued a code orange following the collapse, which is used in the event of an external disaster that creates an immediate demand for services that outstrip the hospital's resources.
The hospital said doctors were also onsite to help with the rescue.