By CBS13 Staff

SACRAMENTO (CBS13) – Authorities suspect fentanyl caused four inmates at the Sacramento County Main Jail to overdose on Thursday, the Sacramento County Sheriff’s Department said on Friday.

The four inmates, who were all housed on the same floor, were found suffering unknown medical emergencies similar to an overdose and administered Narcan to reverse the symptoms, authorities said. The inmates were then rushed to the hospital.

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The synthetic opioid is believed to have been smuggled into the facility by an inmate who was admitted on Thursday, authorities said.

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The sheriff’s office said the four inmates were medically cleared by the hospital within hours and were back at the jail early Friday.

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