Lemark Martin Jr. was arrested just before 1:30 p.m. Sunday, in the 6900-block of South Oglesby Avenue, police said.
He was identified as the suspect who, several hours earlier, battered and killed a 19-year-old woman in the same block, according to police.
CPD said Martin also lives in that block.
Police said the victim was found unresponsive with a head injury inside a South Shore residence in the 6900-block of South Oglesby Avenue around noon Sunday.
She was pronounced dead on the scene, police said.
Area One detectives are investigating.
Martin is due in court Wednesday.
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