CHICAGO — One teenager was killed and another is seriously injured after a shooting on the city’s South Side.

The shooting happened around 10:15 p.m. Monday in the 100 block of West 104th Place. Police said a 14-year-old and 15-year-old boy were walking on the sidewalk when shots were fired.

Family of one of the victims told WGN the two were walking home from a party when they decided to take a shortcut through an alleyway. That’s when someone opened fire from behind them.

The 15-year-old was discovered near an alley with a gunshot wound to the head. He was pronounced dead on the scene.

The medical examiner has identified him as Jimmie Lee Goodwin.

“This killing has to stop,” said Sheila Powell, the 14-year-old victim’s mom. “They are babies, innocent kids. Whoever did this, please reveal yourself.”

The 14-year-old suffered a gunshot wound to the shoulder and graze wound to the head. He was transported to Comer Children’s Hospital in serious condition.

According to family members, the boys were cousins.

No one is in police custody.

According to CPD crime statistics, 132 juveniles have already been shot in Chicago this year, a 33% increase compared to the number of juveniles shot this time last year.

Area Two detectives are investigating.