SEOUL, JUNE 15 (MONDAY) -- Most of the radical student protesters left Seoul's Catholic cathedral this afternoon, ending a five-day stand-off there with riot police that had helped generate the biggest political demonstrations in Seoul since 1980.

The students' departure came two hours after police attacked with tear gas a peaceful crowd of several thousand sympathizers that had gathered outside the church to show support for the students.

About 220 protesters, including 150 students, boarded three buses and two vans, provided by the church, which were to take them to university campuses. The vehicles moved through the crowd amid shouts of "Down with the dictatorship," and many supporters began following the buses.

Fifteen dissidents stayed behind in the cathedral and said they would remain there until their colleagues had returned home safely.

Last night, police had withdrawn from the area and reportedly offered the students safe passage out of the church. Students voted by a narrow margin this morning to accept the offer. But they did not leave immediately.

At about noon they came marching out of the church, touching off spontaneous demonstrations of support by the crowd of mostly office workers on their lunch break.

For close to an hour, the crowd staged a peaceful Philippines-style "people's power" demonstration. Others waved from office windows and showered flowers down on the crowd.

Many in the crowd cheered on the students who had taken refuge in the church Wednesday.

But there seemed to be disagreement among the students, and they went back inside the cathedral.

Shortly thereafter, police charged the crowd outside. People screamed in panic and fled into shops as the tear gas spread.

The students' presence had transformed the church dramatically into a political rallying point for dissidents, and many are reluctant to give it up.

"We want to make these grounds a symbolic bastion of the fight for democratization in our country," Reuter quoted a student leader as saying yesterday. "We will hold out here until our demands are met."

Yesterday, thousands of people in their Sunday best thronged past police lines to the brick cathedral, headquarters of the country's 2 million Catholics. Many were there to attend mass, held almost hourly. Others came to show support for the students or to satisfy curiosity about them.

At a table, people dropped cash for the protesters into a box, with each bill drawing cheers from onlookers. Others watched a student getting first-aid for a chest abrasion and examined a "wanted poster" for President Chun Doo Hwan and his designated successor, Roh Tae Woo.

Outside the church yesterday afternoon, about 2,000 worshipers and students sat on the pavement singing political songs, listening to speeches and chanting a slogan heard endlessly since the start of the demonstrations, "Down with the military dictatorship."

A group of women later marched off the cathedral grounds to a nearby police line to present carnations to the men there.

Other protesters were not so charitable. Just off the grounds of the cathedral, they spotted Culture and Information Minister Lee Woong Hee and an aide, who were apparently gathering first-hand impressions. Students chased them back to police lines.

The Associated Press reported that police checked people leaving the cathedral after masses and that many young people were seen being taken away.

Priests at the church have backed the students since the start of the protests despite differing views on violence and tactics. But yesterday signs emerged that the visitors were wearing out their welcome.

During a mass, a priest asked students to move a noisy rally that was being staged outside the church. He was also seen angrily addressing one student.

Earlier, a church statement announced that the police had offered to give the students safe passage out, but with no promises that they would not be arrested. Priests urged the students to accept the offer.

"The church, because of its mission to maintain normal evangelical activities, has certain limitations to continuing to support you in all aspects, and we appeal to you to return to your homes, schools and workplaces as soon as possible," the statement said.

Police were reluctant to break tradition by raiding the cathedral. However, they wanted to get the students out of the church, because their presence there had triggered demonstrations of support and clashes with police.

Officials had played down reports that the government was considering taking emergency measures to suppress the protests. Dialogue would be used instead, they said.

They also noted that senior leaders of the government party will meet today with the opposition to discuss opening a special session of the National Assembly aimed at resolving the troubles.