(stltoday.com)- Police are investigating after a young woman died outside of the Crystal City Underground during a marathon electronic music concert Sunday.
The concert, which included dancing, magicians and multiple stages with music, continued all night until about 4 a.m. although buses to parking continued to 7 a.m.
Jefferson County Sheriff's Capt. Ronald Arnhart said Tuesday that the victim was 22 and from O'Fallon, Mo. He said he won't release her name until more family is notified.
"She was there with some friends and they were waiting for a taxi to take them to a vehicle," he said. "She sat down and said she wasn't feeling well. She passed out and they called 911 immediately."
He said emergency responders tried to revive the woman just outside the mine entrance at 4:30 a.m. She was rushed to a hospital and pronounced dead there.
Law enforcement officials haven't released a cause of death and said they are waiting for information from the medical examiner.
Bob Kister, an attorney for the venue, said he understood that the young woman died of a possible drug overdose outside the facility early Sunday.
Arnhart wouldn't confirm that she died of an overdose.
"I can't say it's an overdose until I get some information from the medical examiner's office," he said.
The medical examiner said it would take several weeks to get toxicology results.
The victim's family said Tuesday that they were upset by the lack of shared information and the attorney's comments about an overdose.
"How dare he make a statement like that and we don't know," said a distraught family member who didn't want to be named. "I am upset that people supposedly have information that I don't have."
She described the victim as responsible, beautiful and a recent graduate of cosmetology school.
Kister is an attorney for Fiesta Corp., the local company that owns the underground entertainment and event facility. The Underground, once a silica mine, is about a square mile underground.
The concert Saturday night drew about 4,000 attendees, about twice the number expected, Kister said.
"There were no problems inside the cave that I'm aware of whatsoever," Kister said.
He added that the venue has "an absolutely strict no-tolerance policy for underage drinking or use of controlled substances."
The event's promoter, Boogie Knights, provided security. No one from Boogie Knights could be reached immediately for comment.