One man died and scores of others were hospitalized during a weekend music festival at the Gorge Amphitheater in Central Washington, where they allegedly overdosed on the drug molly — a compound billed as a purified, crystalline form of MDMA.

The Associated Press reports that a 21-year-old man from the Seattle suburb of Des Moines was declared dead on Sunday at Central Washington Hospital in Wenatchee. An autopsy was scheduled for Monday.

The 21-year-old was one of seven people treated at the hospital. According to Kathy Hamilton, director of community relations, three of them remain in serious condition.

In addition, the electronic music venue quickly mobilized medical personnel at the Quincy Valley Medical Center, the small, rural hospital closest to the amphitheater, where about 70 concert-goers were admitted and treated for drug- and alcohol-related conditions over the course of the weekend. The hospital, which lacks an intensive care unit, was forced to transfer several of the more serious cases to larger medical centers in the area.

“We deal with the Gorge all summer long,” said Michele Wurl, a spokeswoman for the Quincy Valley Medical Centers. “What we’re seeing this year is much higher acuity — more severe — in the drug use.”

MDMA, also known as ecstasy, is a notoriously volatile member of the amphetamine class of drugs. Its derivative dubbed “molly” is rapidly gaining wide popularity among concert-goers, who often have no clue what the crystalline powder contains.

According to Wurl, molly is usually little more than randomly synthesized cocktail of drugs.

“They don’t even know what they’re taking. They take a hit and 30 to 45 minutes later they take a second. So they get them maxing out one after another. ... We’re not talking about too much drinking or smoking a little marijuana,” she told reporters.

Local deputies handled over 60 calls for service during the festival’s two-day run, and made 23 arrests. According to the Grant County sheriff’s office, charges included possession of controlled substances, trespassing, obstructing a public servant, assault, and disorderly conduct.

“Most in attendance were very respectful people to us and to one another,” Undersheriff Dave Ponozzo told the Associated Press. “I found them to be very social people, many of who went out of their way to thank us for being there.”