An image from video footage shows a top view of a worker at Bouvry Horse Exports shooting a horse. ((Canadian Horse Defence Coalition))

Police say there are no grounds to lay charges after an animal cruelty investigation into a horse slaughterhouse in Fort Macleod, south of Calgary.

The RCMP opened the probe after the Canadian Horse Defence Coalition filed a complaint against Bouvry Horse Exports Ltd., which sells horsemeat to international markets.

The coalition said in April that it had been sent a secret recording showing slaughterhouse workers failing to kill horses with one rifle shot, and animals being left in pain for a prolonged period.

RCMP investigators concluded there was no evidence of intent to cause cruelty to any of the horses, Sgt. Patrick Webb said on Tuesday. No charges will be laid.

In April, Claude Bouvry, one of the owners of the plant, told CBC News that six officials from the Canadian Food Inspection Agency and a veterinarian were always present during the slaughtering process.