THUNDER BAY -- The cause of the fire that damaged Thunder Bay's James Street swing bridge three years ago will remain a mystery.
The Office of the Fire Marshal confirms it has finished its investigation and has been unable to determine how the October 29, 2013 fire began.
Carol Gravelle, a spokeswoman for the Office of the Fire Marshal and Emergency Management, on Monday said investigators have completed their probe "into the origin, cause and circumstances of the fire ... The cause has been classified as undetermined."
Gravelle said the final report was completed in April.
The bridge remains closed to vehicular traffic, but trains resumed using it a few days after the fire.
The City of Thunder Bay and CN Rail are embroiled in a court case over whether the railway is responsible for doing the necessary work to get the bridge fully reopened.
The chief of the Fort William First Nation was surprised to hear how the investigation concluded, saying he hadn’t been told about the findings.
“I don’t get it," said Peter Collins, after learning about the investigation's conclusion during a phone interview with tbnewswatch.com.
"You know, the fire started from something or someone, so it’s very disheartening to say the least that they haven’t found the cause of that fire.”
Collins added “almost three years later, they’re still dealing with the issue.”
Residents of the First Nation continue to detour via Chippewa Road in order to travel to and from Thunder Bay.
