Detectives are investigating four rapes that were reported in Salt Lake City over the weekend.

Salt Lake police said a 22-year-old woman was walking to work about 6 a.m. Sunday near 640 S. 900 East when she heard someone running up behind her. A man wearing a nylon stocking mask knocked her to the ground and dragged her to a secluded area. He then attempted to cover her head with her jacket and cover her mouth so she couldn't scream.The man sexually abused the woman before she was able to break away, police said. The woman was taken to Holy Cross Hospital, where she was treated for minor injuries.

A 42-year-old woman was severely beaten and then raped Thursday afternoon. Officers found the woman naked and unconscious at 540 W. 400 South. The woman was hospitalized in serious condition. Detectives later arrested a 37-year-old man in connection with the incident.

The suspect was also hospitalized with broken ribs and a collapsed lung - injuries he apparently received after an unidentified citizen chased him down. The suspect was released from the hospital Sunday and booked into the Salt Lake County Jail for investigation of aggravated sexual assault.

A Salt Lake woman, 20, reported that she was raped by two men as she was walking through Jordan Park, 1000 S. 900 West, Friday night. The woman said she was on her way to her boyfriend's house when she heard someone following her, a police report stated.

The woman tried to run but tripped and fell. Two men caught up with her and allegedly held her down and raped her. She said one of the men had a knife in his hand and threatened to hurt her if she screamed. Officers later detained two men, but no arrests have been made.

Another rape was reported to have occurred Friday night near the railroad tracks at 800 South and 700 West. A 15-year-old girl told police she was raped when she left a party in the area.

All of the cases are currently under investigation.