Los Angeles » With the chants of protesters wafting into their meeting room and armed police standing guard, the University of California's Board of Regents approved a 32 percent, or $2,500, increase in undergraduate fees Thursday but promised more financial aid to keep needy students from dropping out.

A raucous crowd of about 2,000, including labor union activists and students who traveled from the campuses around the state, faced a large force of university police and California Highway Patrol officers in riot gear outside Covel Commons at the University of California, Los Angeles, where the regents met. Across the campus, another group of about 40 demonstrators occupied a UCLA classroom building, Campbell Hall, and locked themselves inside.

UCLA police reported one student arrested by Thursday evening, but no one injured in the demonstrations. Officials said that Campbell Hall was closed to classes for the day as the sit-in continued and those inside issued e-mail statements blasting the regents.

The 21 regents in attendance approved the fee hikes with little debate after a lengthy committee discussion the previous day. Only student regent Jesse Bernal voted against the increase for undergraduates, and he was joined by the alumni representative regent, Richard Stovitz, in opposing a sharp hike in professional graduate school surcharges.

After the vote, some of the regents were trapped in the building and in vehicles as about 100 demonstrators surrounded the garage. Later, police cleared a path and escorted the officials out in a hurry with students chasing them and shouting, "Shame on you."

Earlier, a group of students marched into Westwood Village, an area near the UCLA campus, and briefly blocked traffic.

Colin Williams, an English major at UCLA, said that as a fourth year student he would be mainly spared of the financial pain that younger students face, but he protested in solidarity. He wore his red tambourine as a hat when he wasn't shaking it.

"We're all the same person; we're all in the same boat," said Williams, who complained the regents were hiding "behind closed blinds."

Busloads of students and union activists descended on Los Angeles.

Among them was Tommy Le, a fourth-year student at U.C. Santa Cruz, who left his campus at 3 a.m. Thursday in a convoy of two buses. Le, an American Studies major, said he was worried about affording the higher charges, beginning with an extra $585 for the rest of the school year.

"It's adding more stress and more burden," said Le, who said he works two part-time jobs and sends money to his family. The fee increase, he said, is "a lose-lose situation."

Ricardo Gomez came from U.C. Berkeley on a bus trip that was financed by labor unions fighting the U.C. system over proposed pay cuts. A third-year student in interdisciplinary studies, he said he has a scholarship that shields him from the fee increase but "lots of my friends don't have that security. So I felt it was my duty to advocate for them."

Given cuts in state funding, the regents said the extra fees will help stave off further course reductions and staff layoffs. They also said at least one-third of the fee increase would go toward financial aid, and they approved a plan that will use U.C., state and federal grants to ensure that students from households with incomes below $70,000 would have their basic education fees fully funded.

After two increases by next fall, basic U.C. undergraduate fees will be $10,302 a year plus about $1,000 in extra campus charges. Room, board and books can add another $16,000.

U.C. President Mark.Yudof said he wanted Californians to know that plenty of financial aid is available. "If people sit around the dining room table and say we can't afford the University of California, then we are in trouble," he said.