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A man already behind bars in California was arrested and charged with the cold-case slayings of five children, all his own and none of them older than 6 months, authorities said Monday.

Paul Perez, 57, is accused of killing the babies from 1992 to 2001, and he was charged with five counts of first-degree murder with special circumstances that could make him eligible for capital punishment, officials said.

A photo of Paul Perez is displayed at a news conference in Woodland, California, announcing his arrest after he was alleged to have killed his five children. KCRA

Yolo County Sheriff Tom Lopez and District Attorney Jeff Reisig, speaking to reporters about the arrest, declined to reveal details of the murders and the investigation — but said DNA evidence, discovered in October, cracked the cold case.

The authorities also declined to say whether Perez had other children or whether the victims came from more than one mother.

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"The investigation in this case uncovered a deeply disturbing, chilling case of infanticide," Reisig told reporters in Woodland, California, about 20 miles northwest of Sacramento and about 80 miles northeast of San Francisco.

"Today, we are announcing charges against Paul Perez for the serial murder of five of his own children, all babies."

Five victims in mass murder case in Yolo County.Father is under arrest. pic.twitter.com/GRVG14fQg6 — Mike Luery (@KCRALuery) January 27, 2020

Authorities said they have the remains of victims Kato Allen and Nikko Lee.

The remains of three other children, officials said, have not been found yet: Mika Alena, Nikko Lee and Kato Krow.

The Yolo County District Attorney's Office disclosed a general timeline of the alleged murders, saying they occurred: on or about Oct. 21, 1992; sometime between Nov. 2 1995, and May 2, 1996; sometime between Nov. 8, 1996, and May 8, 1997; sometime between Oct. 29, 1997, and April 29, 1998; and between April 16, 2001, and Oct. 16, 2001.

It’s believed baby Nikko Perez was discovered in this body of water in rural Yolo county. His father Paul Perez, has been charged with murdering him and four of his siblings. pic.twitter.com/xbNiJnOf6f — Mike Luery (@KCRALuery) January 27, 2020

Three-month-old Nikko Lee's remains were found submerged in an irrigation canal by a fisherman on March 29, 2007, near Woodland, setting off the long investigation, officials said.

'"Cold cases require a unique level of commitment and dedication," said Ed Medrano, chief of law enforcement for the state Justice Department. "The allegations we are discussing today are both senseless, evil and heartbreaking."

Officials said the investigation is ongoing and left the door open that there might be more victims.

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Perez was arrested at a state prison days before he was expected to be released on unrelated charges, officials said.

He began serving a seven-year sentence for vehicle theft in August 2010, before getting four more years for possession and manufacturing a deadly weapon by an inmate, a prison spokesman said.