A CN train derailed inside the Port Huron-to-Sarnia rail tunnel under the St. Clair River Friday morning, with one rail car leaking sulfuric acid.

The rail company said in a statement that about 40 cars derailed in the tunnel, which connects Michigan to Ontario, in “various positions” while “at least one car with dangerous goods is involved.”

CN said in a statement Friday afternoon, a car containing about 52,000 litres of sulfuric acid has leaked as a result of the derailment.

“The sulfuric acid is contained to the site of the derailment and poses no danger to public safety or to the St. Clair River,” company spokesperson Jonathan Abecassis said. “CN is collaborating with the Municipality of Sarnia and St-Clair County as well as the Municipality of Port Huron.”

Sarnia’s Aamjiwnaang First Nation Emergency Planning said in a statement at least two derailed cars were carrying new vehicles which are blocking the Canadian side of the tunnel. Diesel and other motor vehicle fluids have spilled inside the tunnel, according to the agency.

According to Port Huron City Manager James Freed, no injuries have been reported and there’s no threat to public safety as a result of the train derailment.

Freed said U.S. Homeland Security and Emergency Management agencies have been briefed on the incident.

CN also noted there were no fires or injuries reported at the scene of the derailment, adding the cause of the situation is under investigation.

Transportation Safety Board of Canada said Friday afternoon, the agency will dispatch a team to Sarnia to assist in the investigation.

CN said trains are being rerouted, while there’s no estimation as to when the tunnel will reopen to traffic.