SACRAMENTO (CBS13/AP) – Authorities say the man suspected of killing a Sacramento police officer is under an around-the-clock watch after officials say he injured himself in his cell.

Sacramento County Sheriff’s Sgt. Tess Deterding said Monday that 45-year-old Adel Sambrano Ramos banged his head against a bed frame Sunday morning. He was treated at a hospital but returned to the jail 12 hours later.

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Prosecutors still expect him to have his first court appearance Monday afternoon.

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He faces a murder charge that could bring him the death penalty in last Wednesday’s killing of rookie Sacramento police Officer Tara O’Sullivan. He’s also charged with attempting to murder her training officer.

The sergeant says deputies stopped Ramos from harming himself further. He’s now in a barren cell where he doesn’t have access to any items that could be used to hurt himself again.

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