Officials say 15 cars of a Canadian National Railway train have derailed in northeastern Minnesota.

St. Louis County authorities say three of nine cars carrying a hazardous compound derailed, but the cars are intact and there were no leaks. No one was hurt.

CN Railway spokesman Patrick Waldron says the remaining 12 cars that derailed were carrying plastic pellets or were empty.

County emergency services manager Scott Camps says the southbound train had a total of 107 cars. He says the hazardous material is naphthalene. That's best known as a main ingredient in mothballs. It was headed from Winnipeg, Manitoba to Superior, Wis.

The incident happened near Cotton about 20 miles south of Virginia. The cause of the derailment is under investigation.

MPR News' Dan Kraker contributed to this report.