SAN JOSE >> Five people, including two minors, have been arrested on allegations that they attacked a teen boy, knocking him unconscious, then injured his mother when she tried to intervene in what police say was a gang-fueled assault in East San Jose earlier this year.

Officers were dispatched to a shopping plaza near Story and White roads around 1:30 p.m. on Jan. 18 for a report of an assault and robbery, and learned that a teen boy and his mother were shopping when they were confronted by five males, according to the San Jose Police Department.

The group “violently assaulted the juvenile victim, causing him to lose consciousness,” police said. When his mother tried to protect him, the group assaulted her and ran off before police arrived.

An initial investigation determined that the attack was gang-motivated, but police did not specify what occurred to lead to that conclusion.

Gang detectives investigated the attack and identified three men, ages 20, 19 and 18, along with two 16-year-old boys — all from San Jose — as suspects, police said. The 18-year-old man and the two minors were arrested Feb. 12 on suspicion of crimes encompassing robbery as well as assault and gun crimes.

Police said that while serving search warrants at the minors’ homes in San Jose, officers seized two illegal firearms.

The two remaining adult suspects were arrested Tuesday on suspicion of robbery, assault and gang crimes, police said. All five suspects were booked into juvenile hall or jail custody.

Anyone with information for investigators can contact SJPD Detective Eduardo Moreno at 408-277-3835 or by email at 4882@sanjoseca.gov.

Tips can also be left with Silicon Valley Crime Stoppers at 408-947-7867 or at siliconvalleycrimestoppers.org.