A 12-year-old Wahiawa boy assaulted a younger boy Tuesday after the victim refused to give him money, police said.

Police said the 12-year-old, brandishing a knife, demanded money from his 9-year-old victim, who was walking home from school in the Wahiawa area. When the younger boy said he had no money, the older boy started to beat him. A witness, who had been walking home from school with the pair, intervened. The victim went home and told his mother who reported the incident to police.

Officers arrested the 12-year-old on suspicion of first-degree robbery, but he was released pending further investigation into the 5:30 p.m. incident. The victim l complained of neck pain, but refused medical treatment.