Onlookers watch as emergency responders perform CPR on a man who collapsed in the middle of Birch Street at the corner of Knox Street in Lewiston on Wednesday morning. (Russ Dillingham/Sun Journal)

Rescue workers treat a 28-year-old man Wednesday morning who collapsed at the corner of Birch and Knox streets in Lewiston. The man was pronounced dead at the scene. Police said they are investigating. (Russ Dillingham/Sun Journal)