DULUTH  (AP) - Students who own season tickets to the University of Minnesota-Duluth's men's hockey games are being warned to shape up after the school received reports they used offensive chants to taunt the University of North Dakota Fighting Sioux.

Athletic Director Bob Nielson recently sent students a letter that said inappropriate comments directed at officials or other teams could get them tossed from the arena or cost them their tickets.

Students began chanting "smallpox blankets" and other phases during the Feb. 10-11 series against North Dakota.

North Dakota has tried to drop the Fighting Sioux name, but supporters of the mascot recently gathered enough petition signatures to temporarily restore a state law that had required its use.

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