PORTAGE, Ind. (CBS/AP) – Police in northwest Indiana are investigating the death of a 40-year-old man who the coroner says was killed by a pet pit bull.

Porter County Coroner Chuck Harris says Edward Cahill suffered multiple severe bite injuries to his arms and face that resulted in massive blood loss. He says no one witnessed the attack in Cahill’s home in Portage, 50 miles west of South Bend.

But Cahill’s girlfriend arrived home around 8 p.m. Thursday and discovered Cahill on the floor unresponsive. He was pronounced dead at the scene.

The girlfriend told authorities the 85-pound dog suspected in the death, “Fat Boy,” had exhibited aggressive behavior in the past and had been particularly protective of a bone he had been given for Christmas.

The girlfriend “advised she had told Mr. Cahill to euthanize ‘fat boy’ in the past because he was extremely aggressive and was unpredictable,” a Portage Police Department report said.

Fat Boy was removed from the home following Cahill’s, but had to be subdued with a Taser gun first, police said.

Police are continuing to investigate.

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