Updated

A Southern California father pleaded guilty Tuesday to first-degree murder in the death of his 5-year-old son, whose body was found last month after a search lasting 70 days.

Aramazd Andressian Sr., 35, faces 25 years to life in prison when he is sentenced Aug. 23 for the killing of Aramazd Andressian Jr. Prosecutors contend the elder Andressian killed his son to get back at his estranged wife, Ana Estevez.

Andressian's attorney, Ambrosio Rodriguez, said his client entered the guilty plea to avoid the death penalty. Rodriguez said his client confessed to killing his son and told detectives where to find the boy's body, but would not say how or why he did it.

Andressian acted alone and his family is "as devastated as everyone else," Rodriguez said outside Los Angeles County Superior Court in suburban Alhambra.

Rodriguez declined to comment on the theory that Andressian wanted to retaliate against his estranged wife, but said Aramazd Jr.'s death was "not planned."

Estevez attended the brief court hearing, carrying her son's ashes in an urn. She loudly wept in the front row of the courtroom, surrounded by family members -- all holding hands and sobbing.

Prosecutors called the evidence in the case overwhelming, though they didn't elaborate.

"This is a tragedy. Cases like this really tug at your heartstrings," Deputy District Attorney Craig Hum said outside court.

Los Angeles County sheriff's investigators have said they believe the boy was killed April 21 after a family trip to Disneyland. The next day, his father was found passed out in a park and police began searching for the boy.

Andressian had taken prescription pills and was found in a car doused in gasoline in an apparent suicide attempt, sheriff's officials have said.

The boy's body was found on June 30 near Lake Cachuma outside Santa Barbara — about 145 miles away from Anaheim, where Disneyland is located.

Andressian told investigators that he drove to the lake the day his son was killed. Investigators had searched the lake several times before the boy's remains were found.

The Associated Press contributed to this report.

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