Long Beach’s police chief pleaded the public’s help Monday in finding the killer of a 3-week-old baby girl whose body was found in a San Diego County dumpster a day after she was taken from a Long Beach home where her parents and uncle had been shot.

“Every homicide is important, but when you have a homicide that deals with a 3-week-old baby, that just takes it to a different level,” Chief Robert Luna said at a Monday afternoon news conference.

Authorities confirmed Sunday night that the deceased infant who had been dumped in a trash bin at a commercial strip mall in the 600 block of Palm Drive in Imperial Beach (map) was Eliza Delacruz, according to a news release from the Long Beach Police Department.

The San Diego County Sheriff’s Department notified Long Beach police after making the grim discovery Sunday afternoon, and the county coroner’s office confirmed the body was that of Delacruz.

Alongside Long Beach Mayor Robert Garcia on Monday, Luna said police had very limited information to go on. He asked witnesses or anyone who saw anything unusual near the site of the Saturday evening shootings to come forward.

“To take a precious child from home, throw her in a dumpster like a piece of trash is something only a very heartless person would do,” Luna said. “We need to get the coward who committed this violent, senseless act off the street, but we absolutely need the public’s help to do this.”

Luna described the man wanted in the killing and shootings only as dark skinned, possibly Latino or African-American. Police were working with a sketch artist to produce an image of the wanted man, Luna said.

Eliza was kidnapped from the family’s home on the 100 block of West 51st Street (map) after three of her family members were shot and wounded Saturday shortly before 6 p.m., according to police. Luna called the neighborhood where the crime occurred a “highly dense, congested residential area.”

“Somebody had to have seen or heard something,” Luna said. “Somebody knocked on somebody’s door, shot three people and then took a baby out of the house. That isn’t an everyday occurrence.”

The Los Angeles County Board of Supervisors planned to vote on a $10,000 reward for information in the case on Tuesday, Luna said.

Monday evening, Supervisor Don Knabe said on Twitter that he would increase the proposed amount of the reward to $25,000.

The infant’s mother and uncle remained in critical but stable condition at last report. Her father returned home Sunday after being treated at a hospital.

He declined to be interviewed as he walked into the family’s residence with the aid of crutches. He was staying at an undisclosed location.

Long Beach police Lt. Lloyd Cox said the family feared they would be retaliated against if they spoke out.

“They’re afraid of a person coming back again, if they talk, and that they could be the victim of any retaliation,” Cox said. “So they’re terrified.”

The names of the family members wounded in the shooting have not been released.

Based on a preliminary investigation, police believe the incident was not a random act of violence.

“That just doesn’t seem normal, not something we see. And so that makes us think that it’s specific and targeted to this family for some reason,” Cox told reporters Sunday night.

A motive has not been established and police were still working to determine why the family was targeted.

Neighbors told KTLA the family had lived in the neighborhood for about three years. They described the family as “quiet” and “nice,” and expressed shock over the incident.

“This family was very peaceful. There’s no reason this had to happen,” friend Aaron Cruz said.

He added that neighbors were uneasy over the fact that police had no one in custody.

“We’re afraid of this happening again because … a 3-week-old baby was stolen and no one’s arrested, there’s nothing done. There’s no justice yet,” he said. “This is wrong.”

Anyone with a tip was asked to call Long Beach Homicide Detectives Donald Goodman and Mark Mattia at 562-570-7244.

Those who want to provide information anonymously were urged to contact Crime Stoppers by calling 800-222-8477, texting “TIPLA” plus a tip to 274637, or by visiting the website LACrimeStoppers.org.

KTLA’s John A. Moreno contributed to this report.

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