CHICAGO (CBS) — One 17-year-old boy is dead following a drive-by shooting in the Pilsen neighborhood near the Dan Ryan Expressway, while another was wounded overnight after being shot in the Grand Crossing neighborhood.

At least five others were also shot and wounded in the city in the 12-hour period from 5 p.m. Thursday to 5 a.m. Friday, several of whom refused medical treatment and would not cooperate with police

The first victim, identified as Niko Santiago, was standing in the 2000 block of South Canalport Avenue near the soaring Dan Ryan overpass around 10:40 p.m. Thursday. A man drove past in a light-colored sport-utility vehicle and fired shots, police said.

Santiago, of the 900 block of West 18th Street, was dead at the scene, according to the Cook County Medical Examiner’s office. He was shot in the chest and back, police said.

The shooting is believed to be gang-related, police said.

In a separate incident around 11:35 p.m. Thursday, another 17-year-old boy was walking down the street with a group of people in the 7900 block of South Evans Avenue. A gunman approached and opened fire, police said.

The victim was taken in serious condition to Advocate Christ Medical Center in Oak Lawn with gunshot wounds in the cheek and leg, police said. No one else was injured.

No one was in custody in either shooting Friday morning.

In other incidents between Thursday afternoon an early Friday morning:

• A 35-year-old man was shot and suffered a graze wound to the back in the 4900 block of South Wolcott Avenue around 5 p.m. Thursday, police said. He refused medical treatment and would not cooperate with police.

• Around 6:15 p.m., a 19-year-old man was shot in the buttocks when someone stepped out of an alley in the 5000 block of West Concord Place and began firing, police said. He was taken in good condition to Stroger Hospital of Cook County.

• At 6:30 p.m., a 20-year-old man was shot in the arm in the 6400 block of South Bell Avenue, police said. He refused medical treatment.

• Another victim also refused medical treatment, after being shot while struggling with a robber in the 300 block of East 68th Street. At 10:05 p.m., the man was robbed at gunpoint and struggled briefly before the gunman shot him in the left upper thigh, police said.

• Another man was shot and wounded in the leg around 4 a.m. Friday in the 8100 block of South Throop Street, police said. He was hospitalized, but his condition was not immediately learned.

The Sun-Times Media Wire contributed to this report.

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