SAN FRANCISCO — In another blow to Proposition 187, a Superior Court judge Wednesday issued a preliminary injunction preventing the state from enforcing the measure's provisions excluding illegal immigrants from California's public colleges and universities.

The ruling by San Francisco Superior Court Judge Stuart R. Pollak leaves all of the initiatives' major provisions blocked pending trials. Pollak enjoined provisions requiring the state colleges and universities to expel illegal immigrants and report them to authorities.

"There certainly is a sufficient likelihood that the petitioners will prevail in one or more of their theories," the judge said after a three-hour hearing.

Proposition 187, if implemented after the trials, could force California's higher education officials to expel about 13,600 illegal immigrants now enrolled in public colleges and universities and turn them in to federal immigration authorities for possible deportation.

A federal judge in Los Angeles already has enjoined other provisions that would deny illegal immigrants non-emergency health care and social welfare services and require police to check the immigration status of arrestees and those suspected of being in the country unlawfully.

Illegal immigrants now enrolled in community colleges and at University of California campuses pay higher tuition than residents, and the Cal State system also plans to make undocumented students pay out-of-state tuition as a result of a recent ruling in another case.

The lawsuit against Proposition 187's higher-education provisions was brought by undocumented immigrants enrolled in public colleges. Some already have applied to federal immigration authorities for legal status.

The suit contends that the college ban violates the U.S. Civil Rights Act and a federal law requiring public education officials to keep student records private.

Ralph Abascal, a California Rural Legal Assistance lawyer representing the students, told Pollak that the ballot measure already is scaring away undocumented residents from applying to colleges for the fall.

But state Deputy Atty. Gen. Raoul Thorbourne, who argued against the preliminary injunction, said that was precisely what the measure was intended to do.

Thorbourne told Pollak that an order blocking the provisions was unnecessary because the initiative would not be implemented until regulations are in place. "We are in fact jumping the gun," Thorbourne said.