Investigators have launched a probe into the attack that occurred just after 9 a.m.
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The officer was providing coverage during a medical examination in the prison's Adjustment Center housing unit at the time of the attack. The Adjustment Center is one of five units in the prison where male condemned inmates are housed.
We're being told that the officer suffered a significant injury to the face. He was taken to an outside hospital for treatment of several lacerations and is expected to make a full recovery.
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Condemned inmate Anthony Delgado, 49 was sentenced to death in Kings County on June 21, 2000. He was convicted of the first-degree murder of California State Prison-Corcoran inmate Frank Mendoza in 1998 and the first-degree murder of inmate James Mahoney in 1999, also at California State Prison-Corcoran. Delgado has been on California's Death Row since June 21, 2000.
There are 749 inmates on death row in California.