Open this photo in gallery:

Manitoba Premier Heather Stefanson pauses while speaking about the Carberry bus crash during a news conference at RCMP headquarters, in Winnipeg, on June 19.DARRYL DYCK/The Canadian Press

Manitoba RCMP say compiling witness accounts from the fiery bus crash that killed 15 on the Trans-Canada Highway is the most complex part of their investigation as survivors continue to receive medical care for grave injuries.

Superintendent Rob Lasson, in charge of major crime services, the department handing the investigation, said there are typically numerous eyewitnesses during a tragedy of this nature, but all witnesses in this crash were on board the minibus that was struck by the semi-trailer last Thursday. Five of the 10 injured remain in critical condition, largely facing head and orthopedic traumas.

“So, we have to rely on forensic investigations, mechanical analysis of the vehicle and things like that,” said Supt. Lasson during a press conference with Manitoba officials on Monday.

“That’s why it’s taking so long. Normally, we would have more answers because we would have very focused witness accounts very soon after what happened. And this time, we don’t. This is a very unique situation.”

He said investigators have spoken with some of the bus passengers, but he declined to provide an exact number, adding it will be a lengthy process before details are revealed. People who have undergone critical trauma of this kind need time to process, especially when victims have suffered brain injuries, he said.

“Oftentimes their story – it doesn’t come out right away,” said Supt. Lasson.

The RCMP have been unable to speak with the driver of the bus, who is still in hospital, but have taken a statement from the truck driver. Dashcam footage seized by the police shows the truck had the right-of-way when it was heading east on the double-lane thoroughfare before the bus pulled in front of it from the intersecting Highway 5, near the small town of Carberry, 170 kilometres west of Winnipeg.

The bus was carrying seniors, all between the ages of 58 and 88, from the nearby city of Dauphin and the surrounding area on a day trip to the casino. A stop sign was at the intersection, in addition to a yield sign in the median between the opposite lanes. Skies were clear at the time. The bus caught fire after the collision and burned down to its skeleton while the semi-truck was partly jackknifed.

Manitoba Premier Heather Stefanson, who offered her condolences during the Monday news conference, said the province will bring in experts, if necessary, as part of its review of the intersection where the collision occurred. She said an internal review is automatically triggered to ensure the safety of motorists but noted the government is, for now, letting the police investigation unfold.

“We don’t want to rush through this. We want to make sure that we get it right. There are still investigations going on right now. We’ll respect that process,” she said.

“Because of the severity [of the crash], again, I think it’s important that we are willing to go beyond that, bring in experts where needed to ensure safety of people travelling on our roadways is the most important issue here.”

There has been one other fatality at that intersection over the last decade, according to data provided by the Government of Manitoba. In total, 29 collisions have taken place at the crossroads of both highways between 2012 and 2021, resulting in the single fatality, 12 injuries and 16 cases of property damage only. Of the 29 collisions, 22 are listed as motor vehicle collisions, while seven others are listed as crashes involving animals.

Ms. Stefanson announced on Monday that Manitoba Health will reimburse family members affected by the tragedy for any travel, hotel or food costs. Most victims are receiving hospital care in Winnipeg.

Meanwhile, RCMP continue to piece together the circumstances of the crash.

Supt. Lasson said the mechanical analysis of both vehicles is continuing and the major crimes unit is working alongside four forensic collision reconstructionists and two criminal collision experts. He said they continue to work with provincial partners during the process, including officials in the transportation, highways, health and workplace health and safety sectors.

“The methodical, precise investigative steps that are necessary to reach such a conclusion does take time to do properly,” he said.

Autopsies of the deceased have started, he added, and will provide necessary details to investigators and bring closure to their loved ones. “Accuracy is paramount – something that will not be sacrificed in the name of expediency,” he said.

The names of those who died have not been officially announced.

Helen Kufley, 88, was among the victims, her son said in a message on the weekend.

Nettie Nakonechny also died and leaves behind eight grandchildren and five great-grandchildren, her granddaughter Teah Alexander said in a statement to Global News.

Follow related authors and topics

Authors and topics you follow will be added to your personal news feed in Following.

Interact with The Globe