Syracuse, NY -- Authorities have charged two teenagers in the May 23 attack and subsequent death of a 51-year-old Syracuse man outside a South Side market.

A 13-year-old and a 15-year-old have each been charged with first-degree manslaughter in the killing of Michael Daniels, Syracuse Police Chief Frank Fowler and Mayor Stephanie Miner said at a news conference Thursday night.

Daniels was standing alone outside Los Amigos Market at the corner of Cannon Street and West Brighton Avenue around 9:40 p.m. on May 23 when when he was attacked by a group of teenagers. Police said the teens repeatedly punched Daniels and then kicked him in the head while he was on the ground.

He died a day later at Upstate University Hospital.

Fowler said the two teens were taking part in "Knockout," a game in which people randomly target someone on the street and try to knock the person out by punching them.

"A man lost his life because a group of young people decided to play this very dangerous game," Fowler said.

The 13-year-old was charged Wednesday and was being held at Hillbrook Juvenile Detention Center. The 15-year-old was charged Thursday and will be arraigned in Syracuse City Criminal Court Friday morning.

Michael Daniels

Fowler refused to release the names of the teens charged. He said it's the Syracuse Police Department's policy to not release the identities of juvenile suspects, even if they are arraigned as adults because there's a chance a judge could seal the case later on.

Police believe the 13-year-old approached Daniels and threw the first punch and that the 15-year-old joined in after.

Police were not able to question either teenager extensively because both had assigned legal counsel. Fowler said detectives were able to briefly talk with the 13-year-old while his mother was present, but that she later stopped the interview. He said detectives weren't able to talk to the 15-year-old at all.

The charges came about in large part because of a great deal of cooperation from witnesses and those in the community, Fowler said.

Police are now investigating at least four other instances of people being attacked in a similar manner, Fowler said. He declined to say whether the two teens charged in the May 23 incident were also suspected in other attacks.

An investigation is continuing.