WEBSTER CITY, Iowa --
The Hamilton County Sheriff's Office said 1,200 to 1,500 mink were released from their cages early Friday.
The incident happened at a rural residence near Jewell, which is 56 miles north of Des Moines. The Sheriff said "unknown persons opened pens in several buildings and let the mink loose."
The Sheriff's Department, Iowa Division of Criminal Investigation and FBI are investigating the case.
Officials said the incident is considered an act of domestic terrorism.
Anyone with information about the case is urged to call the Hamilton County Sheriff's Department at 515-832-9500.
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