Updated 07/24/14 – 11:58 a.m.

CHICAGO (CBS) — An 18-year-old man has been charged in the shooting death of 11-year-old Shamiya Adams, who was felled by a stray bullet while at a sleepover in West Garfield Park.

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Cook County prosecutors said Tevin Lee has been charged with two separate counts of murder, and one count of aggravated discharge of a firearm, in connection with Shamiya’s death.

Shamiya was at a sleepover Friday night at a friend’s house in the 3900 block of West Gladys Avenue, when a bullet went through an open window, and struck her in the head as she played with friends in a bedroom. She died the next morning at Mount Sinai Hospital.

Police Supt. Garry McCarthy said Lee was trying to shoot rival gang members in retaliation for an earlier fistfight between two 14-year-old boys, one of whom was an acquaintance of Lee’s. He said Lee spotted rival gang members standing in front of the home where Shamiya was attending a sleepover, and opened fire on them, but missed, and a stray bullet killed Shamiya.

“As all too happens with gang violence, an innocent life was taken,” McCarthy said.

Tevin Lee (Credit: Chicago Police)

Tevin Lee (Credit: Chicago Police)

McCarthy said detectives believe Lee was not alone when he shot at rival gang members, and he said the case remains under investigation. Police have not recovered the murder weapon, and did not find any shell casings at the scene, so investigators are not sure what type of gun was used.

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The superintendent said the shooting was another tragic example of young gang members allowing a simple fistfight escalate into a shooting that claimed an innocent life.

“There’s a pattern that we have to break,” McCarthy said. “At the end of the day, you introduce a gun to a fistfight, and this is what happens.”

McCarthy said nine “really good witnesses” helped lead detectives to Lee, including two witnesses who came forward on their own.

“Folks came forward and helped us, which really pushed us along in the investigation,” he said. “It was a lot of information out there in the community, and the community helped us out.”

Shamiya’s mother, Shaneetha Goodloe, moved her family two months ago to try to escape violence. After Shamiya’s death, she asked Mayor Rahm Emanuel to help her move again, closer to her job on Goose Island, and for counseling for both her and her sons, who are 11 and 12.

A fundraiser to raise money for Shamiya’s family was scheduled for Thursday at Fatso’s Last Stand at 2258 W Chicago Ave. The hot dog stand is giving Shamiya’s family the proceeds from all sales between 3 p.m. and 6 p.m. The owner works at the supply company where Shamiya’s mother works, so he wanted to do something for her.

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Memorial services for Shamiya were scheduled for Saturday at 11 a.m. at first Baptist Congregational Church at 1613 W. Washington Blvd.