Three-year-old Alonzo Soeuk was found unresponsive on August 7, 2013, and died that evening at Nationwide Children’s Hospital in Columbus, Ohio. The Franklin County Coroner’s office ruled his death a homicide after investigators determined his injuries were suspicious.

At the time Alonzo lived with his mother, Linda Soeuk, and her boyfriend, Roberto Avina-Casillas, who had been staying with the family about a week. Police say an argument between Avina-Casillas and Linda escalated into a violent assault that resulted in Alonzo’s fatal injuries. A murder warrant was issued for Avina-Casillas, who fled and is believed to have either returned to Mexico or be hiding with relatives in the Columbus area; he remained at large as authorities continued their search.

Alonzo’s mother was left to care for another child, a nine-month-old boy at the time. Anyone who has information on Avina-Casillas’s whereabouts is asked to contact the Columbus Police Department or Crime Stoppers.