Updated

Authorities are awaiting autopsy and toxicology results after a man died and at least seven other people were hospitalized after apparently taking tainted drugs at a suburban San Francisco concert.

Five of the seven hospitalized were in critical condition Monday, while two were in stable condition.

Daly City police say 23-year-old Anthony Mata of Santa Clara died Sunday from a suspected drug overdose at a San Francisco hospital. He and the others fell ill after attending Saturday's "POP 2010: The Dream" music festival in Daly City.

Capt. Cory Roay says Mata may have been under the influence of Ecstasy and methamphetamine. But he says the symptoms are not consistent with a normal Ecstasy overdose.

"They are actually much more serious and life-threatening."

Roay says investigators are still trying to determine who supplied the tainted drugs.