Washington health officials have warned Yakima residents of fentanyl usage after nine people have died after ingesting the drug this year.

The Yakima Herald reports that state health officials issued a public warning earlier this month after three people in the area died of overdoses within days.

Officials said there were 13 deaths related to fentanyl and oxycodone in 2018, up four from the year before.

Authorities said officers have seized up to 20,000 pills at a time in the Tri-Cities and as many as 100 pills in Yakima.

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Yakima authorities said the synthetic opioid is up to 50 times more potent than heroin and 100 times more powerful than morphine.

Authorities say for every one fentanyl death, there have been about 10 people who survived an overdose on the drug.

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