Investigators in California were working on Dec. 1 to identify one or more suspects who opened fire at a child's birthday party over the weekend, killing four people and injuring 11 others.

The shooting erupted at a banquet hall in Stockton, California, where at least 100 people gathered for the celebration, according to San Joaquin County Sheriff Patrick Withrow. He said the incident may have involved more than one shooter and appeared to be targeted.

Three children and one adult were killed in the shooting, the sheriff's office said. The shooting left 11 others injured, and several of them, including multiple children, were taken to local hospitals.

Withrow said at least one person remained in critical condition.

Officials have not publicly released the names of the victims, but families and friends have begun to identify their loved ones.

After the shooting, the Stockton Police Department said it arrested five people, including one juvenile, on conspiracy, weapons, and gang-related charges. Heather Brent, a spokesperson for the San Joaquin County Sheriff's Office, told USA TODAY the arrests were not related to the shooting.

Since the deadly attack, which California Gov. Gavin Newsom called "horrific," law enforcement officials have asked for the public's help in identifying possible suspects, requesting cell phone video and eyewitness accounts. Local officials also announced a $25,000 reward for information leading to the arrest of any suspects.

"We need everyone who has any information on this to reach out to us," Withrow said at a news conference on Nov. 30. "This is the time for our community to show that we will not put up with this type of behavior where people will just walk in and kill children."

How the mass shooting at a child's birthday party unfolded

Withrow said authorities first received reports of gunfire at the banquet hall shortly before 6 p.m. on Nov. 29. At the time, as many as 150 people were there for a child's birthday party.

Three children – ages 8, 9, and 14 – and a 21-year-old were killed in the shooting, according to the San Joaquin County Sheriff's Office. Stockton Mayor Christina Fugazi said the 8-year-old who was killed was a student in the Stockton Unified School District.

She added that the child’s parent also works for the school district.

'My baby was innocent.' Teen remembered by community

Family members identified the 14-year-old killed in the shooting as Amari Peterson, of Modesto, California.

"My baby was innocent," Peterson's mother told the Stockton Record, part of the USA TODAY Network. The outlet did not name the woman. "We were just at the wrong place at the wrong time. Who would have known my baby wasn't gonna come home with me?”

“He was good in everything he did," she said, describing Peterson as loving, caring, and a wonderful athlete. According to a GoFundMe page for funeral arrangements, Peterson was a football player, a basketball player, a brother, son, and cousin.

"He was making plans and looking into colleges of choice. He was NOT involved in any gang activity," the GoFundMe page states. "The only mistake this sweet boy made was being in the wrong place at the wrong time. He was simply being a kid at a kids’ party."

Vigil held in memory of Stockton shooting victims

Hours after the deadly shooting, hundreds of people gathered for a prayer vigil blocks away from the crime scene. Speaking to the crowd, Stockton Vice Mayor Jason Lee recalled a shooting at an elementary school in the late 1980s that killed five children in Stockton.

“We all remember where we were on that day. I don’t want to have those types of memories over and over again," he said. He added: “That trauma lives on forever, and this community is dealing with a lot of trauma."

After the vigil, family members could be seen removing gifts and other items from the banquet where the shooting occurred. One man, wearing a birthday-themed T-shirt, said he was retrieving his daughter's belongings. He asked for privacy.

'This was not a random act'

Withrow said the attack appears targeted, but did not say why investigators believe that.

"We're going to say that we're confident that this was not a random act," he said at a news conference over the weekend. "They walked into this area and was probably looking for somebody in particular. Why they did that, what they're part of, who they are ‒ we don't know."

Dispatch audio reveals emergency response

An emergency dispatcher said multiple 911 calls had come in on Nov. 29 and were reporting that there was a shooting at the address of the banquet hall, according to dispatch audio obtained by the Stockton Record.

One woman told a dispatcher that her son was not breathing, and there were others with injuries, the audio revealed. “I want to advise that there is one down,” the dispatch audio said.

Officials have said it appears the gunfire started inside the banquet hall before moving outdoors. One of the entrances to the building had more than 14 bullet holes.

Multiple vehicles were also towed from the scene, including some that had bullet holes, according to Withrow.

Contributing: Karissa Waddick, N'dea Yancey-Bragg, and Thao Nguyen, USA TODAY; Victoria Franco, The Stockton Record

This article originally appeared on USA TODAY: Suspect sought after deadly California birthday party shooting

Reporting by Christopher Cann, USA TODAY / USA TODAY

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