Chicago rapper Lil Jojo was gunned down Tuesday night (Sept. 4) while riding a bicycle in the city's South Side. According to the Chicago Tribune, the fledgling artist, born Joseph Coleman, died on the scene from a gunshot wound. Officers found him unresponsive on the street.

A witness told authorities that a gunman opened fire from inside of a tan or grey vehicle while Coleman, 18, was on the bike. The rhymer was shot at least one time, reports reveal. He was taken to the University of Chicago Medical Center and pronounced dead by the Cook County medical examiner's office.

A gang conflict could have sparked Coleman's murder, say cops. An investigation is underway.

Chief Keef, 16, who has risen to hip-hop fame due to his hard-hitting anthem "I Don't Like," reacted to the news of Coleman's death in a shocking manner. According to reports, Keef and Coleman were embroiled in a bitter rivalry.

"Its Sad Cuz Dat Nigga Jojo Wanted To Be Jus Like Us #LMAO," Keef wrote on Twitter after learning of his murder. He also posted a tweet that included written laughter.

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