LOS ANGELES — Police believe that some unknown drug was slipped into drinks at a house party attended by college-aged students, sending 12 people to a Washington hospital, authorities said Saturday.

All but one of those hospitalized were women; they may have been targeted at the party in Roslyn, about 65 miles east of Seattle, said Cle Elum Police Chief Scott Ferguson. Cle Elum is nine miles from Roslyn.

Police are investigating whether any sexual assaults occurred.

“”We fear that whoever was doing this was targeting the females,”” Ferguson said.

Initially, police were called to a Cle Elum grocery store parking lot at about 11 p.m. Friday. They found an unconscious female in the back seat of a car. Her friends gave police information that led them to the party, where they found about 50 guests between the ages of 18 and 21. Some of the party guests fled upon the police’s arrival.

“”There was just a lot of general intoxication, period,”” Ferguson said.

Many of the party attendees were students or friends of students at Central Washington University in nearby Ellensburg. Some of the guests were semiconscious and could hardly communicate. Others were unconscious, police said. Some of the victims were in critical condition overnight, but by Saturday evening only one woman was hospitalized; she was in stable condition.

According to interviews conducted by police, the women’s level of intoxication was inconsistent with the number of drinks they consumed.

“”It leads us to believe some sort of drug was introduced into their system,”” Ferguson said.

Students who attended the party told a local television station that they believed a bottle of vodka at the party had been spiked with “”roofies,”” known as a date-rape drug.

Ferguson would not comment on the type of drug consumed.

The university posted a statement on its website Saturday saying it was “”shaken and saddened”” by Friday’s events. The school plans to hold students accountable through the student conduct code, and is hosting community meetings in residence halls through the weekend.

As soon as school officials confirm the identities of the students involved, parents will be notified and a student conduct hearing will be held, the statement said.

Police are awaiting toxicology results taken from blood and urine samples.

“”We’re a very small community, but something of this scale has been entirely unprecedented,”” Ferguson said.