SAN FRANCISCO (CBS SF) — With federal fentanyl seizures soaring over 155% so far this year in San Francisco, the Drug Enforcement Administration Monday issued a health warning over the lethal toll overdoses are taking in the Bay Area and across the country.

San Francisco’s Office of the Chief Medical Examiner says that in July alone, 33 people died of accidental overdoses of fentanyl in the city.

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Santa Clara County is also closely monitoring the number of recorded fentanyl deaths. In 2019, there were 27 recorded deaths. The toll rose dramatically in 2020 to 88 recorded deaths. In 2021, to date through early August, there have been 44 confirmed deaths.

Monday’s safety alert was the first the agency has issued in the last six years and comes during a significant nationwide surge in counterfeit pills that are mass-produced by criminal drug networks in labs containing the deadly drug.

Counterfeit pills have been seized by DEA agents in every U.S. state in unprecedented quantities. More than 9.5 million counterfeit pills were seized so far this year, which is more than the last two years combined.

DEA laboratory testing also has revealed a dramatic rise in the number of counterfeit pills containing at least two milligrams of fentanyl, which is considered a lethal dose.

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“The United States is facing an unprecedented crisis of overdose deaths fueled by illegally manufactured fentanyl and methamphetamine,” said DEA Administrator Anne Milgram. “Counterfeit pills that contain these dangerous and extremely addictive drugs are more lethal and more accessible than ever before. In fact, DEA lab analyses reveal that two out of every five fake pills with fentanyl contain a potentially lethal dose.”

Wade R. Shannon, DEA Special Agent in Charge of San Francisco, said counterfeit pills were flooding into the Bay Area.

“Counterfeit pills containing fentanyl have flooded our region,” Shannon said. “Laboratory testing indicates a dramatic increase in fake tablets containing a lethal dose. Taking a prescription drug not purchased from a licensed pharmacy is extremely dangerous and it may cost you your life.”

In the past year, DEA fentanyl seizures have more than doubled in the San Francisco. Year to date seizures show a 155% increase from the previous year.

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DEA officials said the vast majority of counterfeit pills brought into the United States are produced in Mexico and China is supplying chemicals needed for the manufacturing fentanyl.