Three people died after attending the Hard Summer music festival in Fontana, California this weekend, according to officials.

San Bernardino County Sheriff’s Department spokeswoman Jodi Miller told the San Bernardino Sun that the causes of death of the three victims were not yet known, but that extreme heat had not been ruled out.

Temperatures in Fontana reached 93 degrees on Sunday.

According to the Los Angeles Times, one of the victims experienced a seizure, while another had been complaining of chest pain. Two of the victims died on Saturday, while the third died on Sunday. The three deaths are not suspected to be related.

The victims were identified as Derek Lee, 22, of San Francisco; Alyssa Dominguez, 21, of San Diego; and Roxanne Ngo, 22, of Chino Hills.

“We were deeply saddened to learn about the deaths of three people who attended the festival this weekend,” Hard Summer spokeswoman Alexandra Greenberg said in a statement. “While the causes of the deaths have not yet been determined, we ask everyone to keep them in their prayers. Our sincerest thoughts and condolences are with their family and friends.”

In addition to the deaths, authorities reportedly made 325 arrests, mostly for public intoxication. Approximately 146,000 people attended the event.

The Hard Summer festival — which this year included headliners Ice Cube and Major Lazer — moved to its current location at the Auto Club Speedway in Fontana after two teenagers died at last year’s festival at the Fairplex in Pomona. College students Katie Dix, 19, of Camarillo and Tracy Nguyen, 18, of West Covina died of reported drug overdoses.

Since 2006, at least 24 people have died of drug-related causes at raves organized by Los Angeles-based companies, according to the Times.

 

Follow Daniel Nussbaum on Twitter: @dznussbaum