MARTINEZ (CBS SF) – An inmate at the Contra Costa County Jail in Martinez died Friday morning after suffering an apparent medical problem, a sheriff’s spokesman said.

Around 4:10 a.m., an inmate notified a sheriff’s deputy that his cellmate was unresponsive, sheriff’s spokesman Jimmy Lee said.

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Jail medical staff and deputies responded immediately and began life-saving measures on the inmate, a 46-year-old Pittsburg man.

Contra Costa County Fire Protection District crews arrived at the jail and continued to try to save the man, but he was pronounced dead at 4:27 a.m. Lee said the man had “several existing medical conditions.”

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His name is being withheld until relatives are notified.

The sheriff’s office and Contra Costa County District Attorney’s Office are investigating the man’s death, following county protocol after in-custody deaths.

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