SASKATOON -- Crews from the Transportation Safety Board (TSB) of Canada are beginning their investigation into a fiery train derailment near Guernsey.

Investigators are looking into fragments from the crash, including CP rail cars. The TSB is working on determining the cause, and investigating the train’s reaction to the derailment.

The derailment led to a large fire, with thick black smoke covering the area hours after the incident.

The TSB investigators arrived on Monday, but were unable to attend the scene as flames were still present.

As of Tuesday morning the investigators – from Ontario, Quebec and Manitoba – were allowed on the scene.

HazMat crews, firefighters, RCMP and CP investigators were called to the scene.

In an emailed statement, the province said around 100 responders continue to focus on suppression of the remaining fires. About five to 10 acres have been affected.

Cleanup work is well underway with some damaged rail cars removed from the site and plans are in place to transport the remaining cars when it is safe to do so, the province says.

The Ministry of Environment continues to monitor air quality and there are no advisories. Environmental Protection Officers are monitoring the site and assessing the effects of the incident, the province says.

The highway remains closed and detours are in place.

CP spokesperson Andy Cummings said in a statement that 34 cars of the train, which was hauling crude, had derailed.

There were no injuries and no evacuations, he said. CP re-opened the rail line Tuesday morning once all track repairs and safety inspections were complete.

Federal Transportation Minister Marc Garneau told reporters the train line where the derailment occurred was recently inspected.

“Transport Canada inspected the line in August. CP inspected it visually just a couple of days ago. It was fine. In fact, a train just passed going the other way a few hours before. So we don’t know what happened in that interim period and that’s what the TSB will investigate,” Garneau said.

When asked whether the derailment could have been caused by human error, Garneau said, “It’s way way too early to do this, but I believe a defect occurred with the system, although that’s not final, don’t quote me on that.”

After that statement, the media scrum promptly ended, with Garneau being moved along.