The BBC reports approximately 136,000 hens died when a poultry farm near Edinburgh, Scotland, was broken into and environmental controls tampered with in August.

Officials say the air supply to 12 poultry sheds was turned off, leaving the birds to suffocate. They do not believe the crime, which occurred at Beechgrove Farm, was the work of animal rights activists.

Total worth of the hens was put at £400,000.