Police say John Sanjurjo of Staten Island was arrested Saturday on charges of leaving the scene of an accident.
The child was with a 34-year-old woman and a 7-year-old girl when they were struck by a Mercedes Benz around 8:25 p.m. Friday near a Staten Island deli. Police say the driver sped off after the accident.
The woman and girl weren't badly hurt, but the boy was pronounced dead at Staten Island University Hospital.
Police have identified the slain child as Kyrillos Gendy of South Amboy, N.J.
Authorities say the boy was visiting relatives at a nearby home when the accident occurred.