A 27-year-old woman and her boyfriend have been arrested in the beating death of the woman's 2-year-old son in New York City.

Police say the boyfriend, 31-year-old Reginald Williams, was arrested Saturday on murder charges. The boy's mother, Teresa Foster, was arrested on charges of weapons possession and endangering the welfare of a child. Both are awaiting arraignment.

Aiyden Davis was found unresponsive inside a Brooklyn apartment at about 10:30 p.m. Friday after a 911 call reporting an assault. The boy was pronounced dead at a nearby hospital.

A spokeswoman for the medical examiner says the cause of death was blunt impact injuries to his head, torso and extremities.

A spokesman for Administration for Children's Services says the agency is investigating.