SAN JOSE, Calif. - The former college student known as the "Naked Guy," who gained notoriety in the early 1990s for attending class in the buff, has died in jail, authorities said.

Andrew Martinez, 33, whose stripped-down strolls at the University of California, Berkeley, got him expelled and prompted the city to adopt a strict anti-nudity ordinance, was found unconscious Thursday in a Santa Clara County jail, said jail spokesman Mark Cursi.

Officials are investigating the death as an apparent suicide.

He had been in custody since Jan. 10 on charges of battery and assault with a deadly weapon, authorities said.

In 1992, Martinez organized a "Nude-In" protest at the university. He said he was trying to make a point about free expression.

The message caught on, and nude spottings spiked on campus. Martinez, who landed on national talk shows, was expelled the next year after the university banned nudity.