UPDATED 09/26/11 7:46 a.m.

CHICAGO (CBS) – A teenager has been declared brain dead after being shot on the city’s West Side over the weekend.

As WBBM Newsradio’s Bernie Tafoya reports, Antonio Johnson, 15, now may be able to help others live.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

Police say Johnson and his mother, 37, were shot around 4 p.m. Sunday as they walked up to the front porch of their home, located in the 700 block of North Springfield Avenue in the East Garfield Park neighborhood.

Johnson was hit in the head, and was declared brain dead Sunday night at Mount Sinai Hospital, according to the Cook County Medical Examiner’s office.

He will be an organ donor before being transferred to the Medical Examiner’s Stein Institute for an autopsy.

Johnson’s mother was wounded in an arm, and was treated and released from Mount Sinai, police said.

As of Monday morning, police had no suspects. They say the shots came from someone in an older-model white or cream-colored vehicle, who fired “numerous shots” and then fled north on Springfield Avenue.

The Sun-Times Media Wire contributed to this report.

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