UPDATED 08/13/12 10:24 a.m.

CHICAGO (CBS) — No one was killed in a rash of shootings in Chicago over the weekend, but at least 21 people were injured.

The Sun-Times Media Wire reports the bloodiest shooting happened on Saturday evening, at a gas station in the 6600 block of busy South Halsted Street in the Englewood neighborhood.

Four men were shot around 6:35 p.m. Saturday, in the drive-by incident the parking lot of a Mobil station, police said.

The four men — all in their 20s and 30s — were all listed in good or stable condition at area hospitals early Sunday, despite two of them suffering gunshot wounds to the chest, police said.

Police are seeking a shooter or shooters who fired from a small black vehicle, and no one was in custody early Sunday, police said.

The youngest shooting victim was a 15-year-old boy, who was shot by an armed robber in the 9300 block of South Anthony Avenue, alongside the Chicago Skyway in the Calumet Heights neighborhood.

The boy was walking down the block around 12:45 a.m., when a stranger pointed a handgun at him and announced a robbery.

The boy was shot in the leg while running away, police said. He was taken to Advocate Trinity Hospital in good condition.

The shootings also struck the city’s North Side. In the West Rogers Park neighborhood near Devon Avenue and Leavitt Street, a man was shot in the back and critically wounded late Saturday night.

The 20-year-old man was shot in the back in the 2200 block of West Highland Avenue at 11:24 p.m., police News Affairs Officer Ron Gaines said.

He was shot several times in the back, shoulder and face, police said. He was taken to St. Francis Hospital in Evanston.

Police initially said the man was in stable condition, but his status was downgraded to critical condition early Sunday.

The most recent shootings include a 25-year-old woman who was shot in the leg about 10:45 p.m. Sunday in the 8200 block of South Marquette Avenue, and a 20-year-old man grazed in the back in the 2800 block of North Mason Avenue about 45 minutes later.

And while all the victims of the shootings in Chicago survived, such was not the case in the Cook County suburbs. Five people were shot — four fatally — in the south and west suburbs over the weekend.

Two of the fatal shootings occurred in separate incidents south suburban Harvey and one in Maywood involved an off-duty Chicago Police officer. The off-duty officer fatally shot one of two men who allegedly attacked him after the officer crashed his motorcycle in the west suburb.

The Sun-Times Media Wire contributed to this report.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2012. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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