Authorities in Las Vegas say a homicide victim may have been stabbed to death by bystanders trying to stop him from committing a sexual assault, and they're asking the public for more information.

The Las Vegas Metropolitan Police Department said Wednesday that patrol officers responded to a report of a person stabbed on the 3400 block of East Charleston Boulevard at around 3:34 p.m. Tuesday. Officers found a man in an alley with apparent stab wounds, and medical personnel transported him to UMC Trauma Center where he was pronounced dead.

Officers located an apparent crime scene on the 1000 block of Laurel Avenue. Homicide detectives then "learned that the victim may have been committing sexual assault in a shed in the area," police said.

"A group of citizens ran to assist when they heard a woman's screams coming from the shed. It is believed that the victim was stabbed during the intervention," police said.

All of the people allegedly involved fled the area before officers arrived.

The investigation is ongoing. Police are asking anyone with information to come forward or submit an anonymous tip.

--with reporting by TMX