LOS ANGELES (KCAL, KCBS) -- The U.S. Department of Justice's Los Angeles office filed charges in what could be the nation's first death-resulting criminal case involving a synthetic opioid that prosecutors say is "up to three times more powerful than fentanyl."

On Thursday, federal prosecutors announced the sole count of distribution of protonitazene resulting in death against 21-year-old Benjamin Anthony Collins, a resident of LA County. He faces a mandatory minimum sentence of 20 years in prison if convicted. The harshest possible punishment for this charge is life in prison.

The Justice Department claims that Collins knowingly and intentionally sold the pills to a 22-year-old man on April 19, 2024, according to the indictment.

The man took some of the pills in the front seat of his car soon after allegedly buying them from Collins. The Justice Department said he died quickly after taking the drugs. His mother found him dead inside his parked car outside of her home.

Fentanyl is 50 times stronger than heroin and protonitazene is three times more powerful than fentanyl, prosecutors said.

According to the Center of Forensic Science Research and Education, the novel opioid entered the illicit drug market in North America sometime before May 2021. The Justice Department believes this is the first death-resulting criminal case involving protonitazene in the nation.

According to the U.S. Centers for Disease Control and Prevention, opioid overdose deaths have dropped to their lowest numbers in three years, but remain at higher levels than before the COVID-19 pandemic.

The agency's provisional figures show that there have been 75,091 opioid overdose deaths in the U.S. for the year ending in April. Last summer, the U.S. reached more than 86,000 estimated annual deaths.

Pre-pandemic, there were fewer than 50,000 fatal overdoses a year.