SACRAMENTO, Calif. -- Prosecutors charged a father Monday with three counts of first-degree murder in the deaths of his children, saying a belt was used in two of the killings.

Prosecutors filed the charges against 32-year-old Robert William Hodges in the deaths of 11-year-old Kelvin Hodges, 9-year-old Julie Hodges and Lucas Hodges, nearly eight months.

Hodges pleaded not guilty during his first court appearance.

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Yolo County District Attorney Jeff Reisig said the two older children were killed with a belt but would not say how it was used or give other details, including a motive.

The charging documents don't say how the infant was killed.

Prosecutors also charged Hodges with the attempted murder of his wife, Mai Hodges, after she called police Wednesday to report she had been assaulted.

A neighbor who came to the aid of Mai Hodges told CBS Sacramento she watched her husband leave his family's apartment the night of the murders, and that he showed no emotion.

"He seemed content," she said. "He seemed content. Absent. He was not in a rage."

Arriving officers found the three children dead and Robert Hodges missing; he was arrested hours later.

Authorities said Monday that Hodges was ordered held without bail for an Oct. 2 court appearance.

Deputy public defender Ron Johnson, who represented Hodges in court, did not immediately return a telephone message seeking comment.

Hodges faces three special circumstance allegations that could bring the death penalty if he is convicted - two of lying in wait plus multiple murders.

"We have not yet determined if we intend to seek the death penalty," Reisig said at a news conference. The decision is months away after prosecutors weigh the circumstances of the case.

The prosecutor also said the facts of the crime would not be released to ensure that Hodges receives a fair trial.

Police have said Mai Hodges did not witness the slayings.

Relatives and neighbors have said there were no apparent problems or abuse in the marriage. Police said they had no history of calls to the family's apartment, and Robert Hodges had no significant criminal record.