PLACENTIA (CBSLA) — Three men who police say thought they were ingesting cocaine actually overdosed on fentanyl.

Officers were called to the parking lot of Mr. K’s Liquor, 615 W. Orangethorpe Ave., at about 5 p.m. Monday and found three men unconscious and unresponsive in a vehicle. Firefighters were called out treat the men, which included administering Narcan, an anti-opiate medication, according to Placentia police.

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After several doses of Narcan, the men regained consciousness and were taken to a hospital for further treatment.

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Police say the three men all worked at an Anaheim-based landscaping company.

Drug paraphernalia and a white powder that officers believed to be fentanyl was found at the scene. The men confirmed to the officers that they had ingested the powder believing it to be cocaine.

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Police describe fentanyl as a powerful synthetic opioid analgesic that is similar to morphine, but up to 100 times more potent. In December, four people were hospitalized just from being exposed to fentanyl at a Woodland Hills hotel.