BILLINGS, Mont. (AP) — Yellowstone National Park has started shipping hundreds of wild bison to slaughter for disease control as a quarantine facility that could help spare many of the animals sits empty because of a political dispute.

Park officials say 15 bison originally slated for the quarantine on the Fort Peck Reservation were instead loaded onto trailers Wednesday morning and sent to slaughter. Hundreds more will be shipped in coming days.

Montana officials oppose transferring bison to the quarantine.

Fort Peck's Assiniboine and Sioux tribes built the facility with room for 300 animals in hopes of using it to establish new herds across the U.S with Yellowstone's genetically-pure bison.

Tribal Chairman Floyd Azure says state and federal officials "slapped the Fort Peck tribes in the face" by not using the facility.