VIDEO: Man accused of killing Sacramento Police Officer Tara O'Sullivan appears in court

SACRAMENTO, Calif. -- The man charged with murder in the killing of rookie Sacramento Police Officer Tara O'Sullivan appeared in court Monday afternoon.

Adel Sambrano Ramos entered with a large bandage on his head.

He is now under an around-the-clock psychiatric watch after officials said he injured himself in a jail cell.

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Ramos was treated at a hospital and returned to jail after smashing his head against a bed frame on Sunday morning, said Sacramento County Sheriff's Sgt. Tess Deterding.

Ramos, 45, could receive the death penalty in Wednesday's slaying of Sacramento Police Officer Tara O'Sullivan. He's also charged with attempting to murder her training officer and with possessing two illegal assault-style rifles.

Deterding was not sure if he needed stitches, but "obviously given the length of time - only 12 hours - he was cleared for further incarceration, so nothing major."

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The attorney expected to handle Ramos' court appearance, assistant public defender Diane Howard, did not immediately comment.

He's now in a psychiatric wing of the jail "where we've taken even further precautions to make sure he doesn't hurt himself like that," Deterding said.

He is provided a thin mattress and what is known as a suicide smock instead of regular jail garb: "It's tear-resistant, things like that, they can't turn it into a noose," she said. There are mental health employees in the unit.

Memorial services for O'Sullivan, 26, are set for Thursday at the Bayside Church's Adventure Campus in Roseville, California. She was shot during a domestic violence call as she and other officers helped a woman collect her belongings from the garage of a North Sacramento home.