Authorities in northwest Iowa say a case of criminal mischief killed hundreds of pigs. Sioux County Sheriff’s deputies say it happened in a confinement facility located five miles south of Rock Valley.

At least one person is believed to have entered the building and tampered with the climate control system sometime between 3 p.m. Tuesday and 1 p.m. Wednesday. Around 475 pigs died – each weighing about 280 pounds.

Anyone with information that could help authorities track down whomever committed the crime is asked to call the Sioux County Sheriff’s Office.