BUTLER, Pa. — There’s a large emergency response at a Butler home after three people were found dead. Channel 11 saw firefighters, police and medics at a home on College Street on Tuesday afternoon. We’ve learned that three people were found dead from possible carbon monoxide poisoning. The deaths are under investigation.

Authorities believe carbon monoxide poisoning caused the deaths of three people found in a western Pennsylvania home this week, but investigators have yet to determine what led to the deadly exposure.

Officers said they were called to 109 College Street in Butler City for reports of a dead person. They found that person and two other people dead from suspected carbon monoxide poisoning. Two other people were taken to a hospital from the scene.