COLUMBUS, Ohio (AP) _ Police were searching for a 19-year-old man accused of murdering a preschool boy by punching him repeatedly in the chest earlier this year.

Authorities did not explain Thursday how Robert Overton III knew 4-year-old Antwan Bowman or what he might have been doing at the boy's home.

Antwan Bowman was found unresponsive at his home and taken to a hospital, where he died March 8, homicide detective Anne Pennington said in a court complaint. The county coroner blamed the death on blunt-force trauma.

Overton is also wanted on a misdemeanor drug-abuse charge, court records show. His trial in that case is scheduled for June 5.

The boy and his three siblings were removed from their parents' home in April 2006 after allegations of mistreatment, said Kay Marshall, a Franklin County children services spokeswoman. The agency worked with the family and the children were returned in February, a month before Antwan's death.

Telephone numbers for Antwan's parents, Antwan Bowman Sr. and Monica Dumas, are unlisted.