A new round of violence erupted in four towns in the occupied West Bank today, with Israeli troops firing on rock-throwing Palestinians, killing two students and wounding others.

A third Palestinian died in an Israeli hospital of a gunshot wound received in a demonstration on April 12, bringing to 15 the number of protesters reported by Arab sources to have been killed by troops or armed civilian settlers since widespread protests began on March 18 after the first of three West Bank mayors was summarily removed from office by Israeli authorities for alleged incitement.

An Arab news agency, the Palestine Press Services, said that in addition to 15 killed, it had a list of more than 200 protesters wounded in clashes with Israeli forces since March 18.

An Israeli Army spokesman, in response to an inquiry, said nine Arab youths have been killed by Army gunfire since March 18 and two soldiers have died, one stabbed to death in Jenin and another killed by a hand grenade thrown by Arabs in the Gaza Strip. He said 90 Arabs have been wounded by gunfire and 33 soldiers and 16 Israeli civilians have been injured in rock-throwing clashes.

The wide disparity in the reported numbers of Arabs wounded has been attributed, in part, by Israeli military sources and Palestinians to a reluctance by youths lightly wounded to go to a hospital out of fear that they will be interrogated by security forces. Many of them obtain treatment in private clinics instead, the sources said.

The clashes today, which followed more than a week of relative calm, underscored the chain-reaction nature of much of the violence in the West Bank, where reports of confrontations travel fast and sometimes fuel further confrontations.

The trouble began about 7:30 a.m. in Halhoul, on the outskirts of Hebron. Students raised a Palestinian flag, set fire to gasoline-soaked tires and erected rock barricades across the Jerusalem-to-Hebron road.

Palestinian sources said that when an Army patrol arrived, the youths threw rocks and bottles at them.

Israeli authorities said the soldiers first tried to disperse the crowd with tear gas and warning shots fired into the air but that when the rock-throwing "became risky to the troops," they fired into the crowd, aiming at the legs.

One student, Jamal Mousa Shalaldeh, 17, was shot in the throat and died on the way to a hospital. The Army command said two other students were shot, but Palestinian sources said 15 were shot, most of whom sought treatment at private clinics for light gunshot wounds.

Shortly after Shalaldeh's death, word reached his home village of Sair, a few miles away, and rock-throwing demonstrations erupted there, prompting security forces to impose a curfew, military sources said. The Army command said that at about 10:30 a.m. the curfew was broken and an Army patrol clashed with rock-throwing youths, opening fire and killing Abdel Rahaim Abdel Jaradat, 17. Halhoul and Sair remained under curfew tonight.

Soon after Jaradat was killed, scores of youths took to the streets in Hebron, stoning Army vehicles and cars driven by Jewish settlers until they were dispersed by troops firing warning shots.

In Bethlehem, about 15 miles to the north, Arab youths attempted to storm the police station in Manger Square, opposite the Church of the Nativity, and were dispersed by tear gas and warning shots, the Army said. Arab sources in Bethlehem said two youths were wounded by gunfire, but the Army spokesman said he had no information about injuries there. Demonstrators also were dispersed by tear gas at Bethlehem University.

The protests quickly spread to Nablus, about 30 miles north of Jerusalem, where youths smashed windows of Israeli cars and attacked an Army foot patrol with rocks, the Army said. A spokesman said troops used tear gas and rubber bullets before firing at the protesters' legs with automatic rifles, wounding two persons. Palestinian sources said eight people were wounded by gunfire, including a woman shot in the abdomen.