SANTA CRUZ (CBS SF) — Investigators are looking into reports from female students at the University of California at Santa Cruz that their drinks were spiked with drugs at parties.

One of the students reported being sexually assaulted after her drink was spiked, and city of Santa Cruz police are investigating that incident, university Police Chief Nader Oweis said.

At least three students have made reports to university police about drinks being spiked at parties both on and off campus since last week, Oweis said.

It is not yet known what drugs are being placed into the drinks, but the effects include high levels of intoxication, nausea and vomiting, Oweis said.

“They get one beer and that one beer feels like they had four beers,” Oweis said. “That’s how they get sick.”

University police posted a message on the department’s website urging students to be cautious at parties, in bars and elsewhere, and to never drink anything out of a common punch bowl, Oweis said.

Police also warn students not to leave their drinks unattended, not to accept open beverages from anyone they do not know well and trust, and to remember that many drugs placed into drinks are colorless, odorless and flavorless, Oweis said.

“If someone offers to buy you a drink, go up to the bar with them and accept the drink,” Oweis said.

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