SEOUL, JULY 5 -- The death of a student demonstrator early this morning touched off the first clashes between students and riot police here since the government last week calmed nationwide protests by promising free elections in the fall.

Lee Han Yol, 21, a Yonsei University student who had been in a coma since being struck on the head by a police tear-gas grenade June 9, died shortly after midnight today. He thus became the first student to die as a result of the angry demonstrations that nearly paralyzed South Korea last month.

More than 2,000 students late this afternoon fought riot police briefly near the Yonsei campus, scene of almost daily street clashes this spring. The rest of the city remained calm.

However, Lee's death injected another emotional element into the nation's fragile efforts to enter a new era of democracy and conciliation. A larger rally is planned for Monday, and the main opposition party said it will suspend work on drafting its proposal for a new constitution until after Lee's funeral Thursday.

The depth of the gulf remaining between the government and some of its opponents was evident today when Yonsei students tore, petal by petal, then trampled and finally burned a funeral wreath that they said had been sent by Roh Tae Woo, chairman of the ruling Democratic Justice Party.

Roh, an ally of President Chun Doo Hwan, stunned and delighted many of this nation's 42 million citizens last Monday when he gave in to opposition demands for direct presidential elections, freedom for political prisoners and increased freedom of the press. Chun, whose decision last April to suspend talks with the opposition on a new constitution helped ignite the demonstrations -- mostly by students -- endorsed Roh's concessions in a nationally televised speech two days later.

{The government Monday afternoon began freeing political prisoners, by releasing 177 persons arrested during recent antigovernment demonstrations. They included Yang Soon Jik, a vice president of the opposition Reunification Democratic Party, and 11 other leaders who organized massive protests that began June 10 and lasted 18 days.}

The resumption of protests today and suspension of work on the constitution were not seen as a rejection by the main opposition party of the government's package of reforms. The opposition party does not control student protesters.

Many activist students, who made up the core of the protests that led to Roh's June 29 turnabout, say they do not trust Roh, a former general who helped Chun seize power in 1980 and hopes to succeed Chun as president next year.

Despite the bitterness evident in recent street protests here, students and police alike have tried to avoid lethal force, with both sides eschewing firearms. Lee's death, therefore, following the earlier deaths of one policeman run over by a bus and one demonstrator who fell from a bridge, was viewed as a potentially seminal event.

The government seemed unsure how to respond to the death and to student efforts to turn the young victim into a political symbol. Riot police this morning first blocked all entrances to the university and nearby Severance Hospital, where Lee died, then withdrew to allow mourners to the scene. The police finally returned to block with volleys of tear gas an attempted march off the campus.

Student leaders claimed that police also attempted unsuccessfully to remove Lee's body from the hospital in order to arrange a small and unpublicized funeral. There was no independent confirmation of that charge.

Seoul's chief of police, Cho Jong Suk, expressed sorrow at Lee's death without accepting any blame.

"It's deeply regrettable that the police had to see such an unfortunate accident happen while exerting their best efforts to maintain public peace and order," he said.

Kim Young Sam, president of the opposition Reunification Democratic Party, who visited the hospital today to view Lee's body and pay respects to his family, said the government should "apologize truly" for Lee's death. "Lee Han Yol will be remembered forever as a martyr for democratization," he said.

Kim Dae Jung, South Korea's other chief opposition leader, visited the hospital as well. "What makes me most sad is that Lee passed away without knowing the great national victory we have won toward democracy," he said.

Students and other sympathizers lined up during the day for a chance to bow their heads to a photograph of the dead student that stood on a makeshift altar with candles and incense in front of the Yonsei student center.

"He could be me," said one student, a Yonsei economics major who asked not to be identified. "I could be shot by a tear gas canister."

Another student said he hoped Lee's death will reenergize a movement that was cast adrift by the government's surprise offer of reforms. Many in South Korea's middle class, who supported the students in their demonstrations last month, appear eager for the political parties to negotiate a new constitution and hold what would be South Korea's first genuinely contested election in 16 years.

"The citizens want to believe Mr. Roh, but we students believe that real democracy has not come yet," one student said. "If he were a real democrat, he would have decided before."

Students listened to a series of antigovernment speeches laced with anti-Americanism; many students blame the United States for supporting what they consider a military dictatorship. Several said they were angered at hearing that U.S. Ambassador James R. Lilley greeted Roh yesterday at a Fourth of July reception with effusive compliments, calling him a "hero" and creator of democracy. An embassy spokesman said he did not know whether those reports were accurate.

After trampling the flowers from Roh's wreath, students and a few supporters, including mothers of jailed students, attempted to march off campus. They crossed one intersection, then shoved and shouted at a phalanx of heavily shielded policemen, who scattered them with tear gas.

The police allowed the marchers to return to Severance Hospital, where students said they would maintain an all-night vigil around Lee's body.

Government officials, meanwhile, said they expect to release 160 political prisoners Monday. Chun last week promised freedom for most students and opposition politicians now in jail.

Washington Post correspondent John Burgess contributed to this report.