NEWARK (CBS 5/AP/BCN) — A 17-year-old star football player has been stabbed to death in Newark and the teen’s mother suspects the killing has something to do with a recent incident at a football team party.

Newark police Capt. Bob Douglas said that Justice Afoa, an All-Mission Valley Athletic League defensive lineman at Newark Memorial High School, was stabbed at a intersection around 3:42 p.m. Wednesday. It was the city’s fifth homicide this year.

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Afoa’s mother said that a recent incident at a team party involving two non-players may be linked to her son’s death.  She says the pair were beating a cheerleader and her son jumped in to stop the attack.

Justice Afoa was a defensive lineman at Newark Memorial High School before transferring to Bridgepoint Continuation High School in the fall.

He was named to the second-team all-league in the Mission Valley Athletic League last school year, Newark Memorial High School athletic director Rich Swift said.

In addition to his athletic ability, Swift said team members and friends appreciated Afoa’s upbeat attitude.

“He was a good guy,” Swift said. “If you were around him, you just felt better. He was positive, happy-go-lucky and playful.”

Afoa dreamed of playing college football, Swift said.

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He transferred to Newark Memorial High in 2009 after moving to Newark from East Palo Alto. When he lived in San Mateo County, he attended Carlmont High School in Belmont.

“It seems that there was some sort of altercation that occurred to which a large group of people were witnesses,” Newark police Cmdr. Bob Douglas said. “However, they have been reluctant to provide information. We need their help to put whoever was responsible under arrest.”

KCBS’ Tim Ryan Reports:

Two men in black clothing, including hooded sweatshirts, were seen running from the area, but police did not have any suspect leads as of midday Thursday, Douglas said.

Students and family members held an impromptu memorial near the scene of the crime today, Swift said.

Swift, who spent the morning meeting with students and counselors close to Afoa, said he admires the school’s response to the tragedy.

“I’m so proud of how they have stood together,” Swift said. “They have been very supportive of each other.”

Anyone with information about the stabbing is asked to call Detective Sgt. Mike Carroll at (510) 578-4247 or the anonymous witness hotline at (510) 578-4000, ext. 500.

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