Five people, including a 13-year-old girl, were injured after being shot in separate shootings on the far South Side this afternoon, police said.

The first shooting happened at about 3:21 p.m. at a gas station on the 9900 block of South Vincennes and resulted in the shooting of the girl and a 44-year-old woman who were inside their car, said Chicago Police News Affairs Officer Daniel O'Brien.

As the shooting occured, an off-duty Chicago police officer who was still in uniform after ending his shift happened to be in his vehicle at the intersection and witnessed the shooting, said O'Brien.

At that point, the officer pursued the offenders to the 9800 block of South Throop Street where one of the men fired at the off-duty officer who fired back at the offender, O'Brien said. Neither the officer or the offender were struck, O'Brien said.

The females managed to drive themselves to 103rd and Halsted Streets where they were taken to Advocate Christ Medical Center in critical condition, police said.

A male offender is in custody and police were canvasing the area with a helicopter and were searching for two other male offenders.

In the second shooting which occurred at 4:31 p.m., three men sustained gunshot wounds on the 10600 block of South Prarie Avenue, O'Brien said.

Two of the men were 23-years-old, said O'Brien. One of the men was shot in the groin and buttocks and the second man was shot in the calf and foot, police said. Both men were taken to Christ Hospital where their conditions had stabilized.

A third 23-year-old man sustained multiple gunshot wounds and was taken in critical condition to John H. Stroger, Jr. Hospital of Cook County, police said.

The men were shot after a man in his 20s approached the men on foot and shot at the victims, O'Brien said.  At that time, another off-duty officer witnessed the shooting and chased the shooter on foot as the offender tried to flee down an alley, O'Brien said.

At that point the officer ordered the shooter to stop when the offender fired shots at the police officer who then fired back, O'Brien said. Neither the officer or the offender were struck, police said. The man fled east down the alley and then southbound and escaped, O'Brien said.

Area south detectives were investigating both shootings, O'Brien said.

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