POMONA, Calif. (AP) — Two young women died from suspected drug overdoses at a popular weekend music festival at the Los Angeles County fairgrounds, prompting calls for an investigation and concern over the use of drugs at youth-oriented events.

The women were found unresponsive on Saturday at the HARD Summer music festival in Pomona, about 30 miles east of downtown Los Angeles.

Tracy Nguyen, 18 of West Covina and Katie Dix, 19, of Camarillo were hospitalized but died within hours of each other, authorities said.

The deaths appeared to be due to drug overdoses but autopsies were planned, coroner’s Lt. Fred Corral told the Los Angeles Times.

The two-day festival had sellout crowds of about 65,000 each day. The event was held at the Fairplex in Pomona, on land mostly owned by the Los Angeles County government, the Times said.

County Supervisors Michael D. Antonovich and Hilda Solis said they want to know whether the festival was managed in a way that protected the event-goers and would request an investigation.

Solis planned to introduce a motion at Tuesday’s board meeting to explore prohibiting similar events on county-owned land until an investigation is conducted.

Fairplex officials are “aware of the risks” and beef up safety measures when large events are held at the site, spokeswoman Renee Hernandez told the Times.

“We have protocols in place and our event promoters supplement Fairplex medical and security staffing during highly popular events in consultation and coordination with community public safety leaders,” she said.

Drugs and alcohol are not uncommon at music festivals, especially youth-oriented events.

“It is unfortunate that this kind of tragedy happens. People get carried away,” said Oscar Mendez, 19. “People try to fit in and they don’t know their limits.”

At least 19 people have died from overdoses or in drug-related incidents involving music festivals in California and Las Vegas since 2006, the Times said.