A construction worker was killed on Tuesday after he was trapped and crushed under heavy equipment at the future site of a subway station within York University's campus.
Five others were injured when large construction machinery fell on top of two smaller pieces of equipment, one of which contained the man who died, police said.
Another man was stuck inside heavy machinery for at least 90 minutes, police said, while his fellow workers and emergency crews talked him through the ordeal. He was taken to Sunnybrook hospital with serious but non-life threatening injuries including a broken femur.
"[The]investigation is now starting," said Sgt. Simon Fraser, at the scene in front of the Seymour Schulich Building, hours after police received a call for the industrial incident at about 2:30 p.m.
"My concern throughout this was controlling the scene, making it as safe as possible and getting done what we needed to get done as quickly as possible. The investigation is going to go for days, weeks, if not months."
Behind the dozens of emergency and construction workers, a white crane was trying to pull off a large yellow drilling rig, which had its tracks in the air.
Police have not released the victim's name pending notification of his family. He was pronounced dead at the site and his body remained under the wreckage hours after the accident as the scene was investigated.
The scene was under the control of the Ministry of Labour by Tuesday evening, police said, and it's expected to be closed off until Wednesday.
An investigator and an engineer have been assigned to the scene, said ministry spokesman William Lin. They're tasked with piecing together what happened, determining whether charges should be laid and prescribing preventive measures.
Neither police or the ministry released the name of the construction company that the workers were employed by.
TTC spokesman Brad Ross said the collapse occurred at the future site of a new York University subway station, part of an extension of the Spadina subway line from Downsview Station north into York Region.
"The construction was being performed by a contractor under contract to us and they were doing some work on the site in preparation for the construction of the station itself," Mr. Ross said. "[There was]no tunnelling under way right now at that location, but there will be eventually."
The new York subway station is a joint venture of Spanish-based construction and engineering firms Obrascón Huarte Lain and FCC Construcción. Those firms are responsible for all safety measures at the site as well as any subcontracting, Mr. Ross said.
"All contractors ... must develop a safety plan, so clearly the Ministry of Labour will be looking at all of that and we'll be working with them and providing whatever they need as part of their investigation," he said.
A York University spokesman said the site was licensed by the TTC and not officially part of campus.
The university is in the midst of a long-term construction boom to accommodate rising enrolment and update aging facilities, including a major project to extend the University-Spadina subway line into the heart of its campus, in Toronto's north end.
Behind the yellow and red emergency tape surrounding the scene on Tuesday afternoon, students peered as police, paramedics and firefighters tried to free the injured.
"It's our campus. There are workers who are doing something to benefit future students coming here," said Poly Hughes, a second-year masters of education student. She noted that since it's the fall reading week there weren't too many students on campus.
Police said counsellors will be at the school in case there are any student witnesses want to talk to someone.
With files from James Bradshaw