SAN JOSE (CBS SF) — Overdoses of the potent drug Fentanyl have been spiking in Santa Clara County over recent weeks, resulting in numerous calls for medical assistance and murder charges being filed against a San Jose man related to the death of a Santa Clara teenage girl.

On Saturday, the Gilroy Police Department said it officers had responded to an increased number of drug overdose cases over the last week.

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“Acting on their training, the responding officers were able to successfully revive the individuals by administering NARCAN,” Gilroy police said in a statement. “Although the drug(s) associated to these overdoses is unknown at this time, it is believed they are fentanyl related.”

Last week, Santa Clara prosecutors announced that a 22-year-old San Jose man had been charged with murder for allegedly selling pills containing fentanyl to a teenage couple that lead to an overdose death.

The Santa Clara County District Attorney’s Office said it has charged Anthony Minjares with murder and numerous narcotics-related felonies in connection with an 18-year-old Santa Clara girl’s death. If convicted, he could be sentenced to life in prison.

Investigators said the girl and her 17-year-old boyfriend bought powerful fake opioid pills through Snapchat.

The two teens – thinking they were buying Percocet – bought the counterfeit pills that contained fentanyl – not oxycodone – as well as other drugs allegedly from Minjares on April 5.

By that evening, the male victim was unresponsive. His life was saved by quick-acting firefighters using Naloxone. The female was found hours later that night in an upstairs bedroom. She could not be revived.

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Prosecutors charged Minjares with murder under the theory that he advertised and sold the fake pills despite knowing they were extremely dangerous.

“The destructive and devastating power of illegal opioids has ravaged many parts of this country,” District Attorney Jeff Rosen said. “The recklessness of those who peddle these extremely dangerous and illegal counterfeit drugs is tantamount, legally and ethically, to murder.”

Fatal fentanyl-related overdoses have spiked in Santa Clara County in recent weeks. Fentanyl is a powerful synthetic opioid that is far more toxic than most other opioids and is the leading cause of overdose deaths in America.

Officials issued a warning that they are seeing a potentially deadly variant of the drug flooding the illegal drug market.

On April 9, Santa Clara police investigators arrested Minjares, seizing drugs, paraphernalia and cash.

Fentanyl is approximately 50 to 100 times more toxic than morphine. Just a few grains can cause a fatal overdose. Illicit fentanyl is sometimes pressed into pills made to look like other prescription pills (like oxycodone, hydrocodone, Xanax and others.)

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In Santa Clara County, fentanyl is especially prevalent infake generic pills designed to look like Mallinckrodt-manufactured 30 milligram oxycodone hydrochloride (called “M30s,” “M-box-30s,”“pressed blues,” “blues,” “Oxy,” Mexican Oxy” and other names).