Israeli troops arrested dozens of Palestinians today during a search of the West Bank city of Jenin for militants involved in a suicide bombing, and a U.S. envoy left the region with neither side optimistic about the latest peace proposal.

In an army operation that began Friday, soldiers imposed a curfew on the 50,000 residents of the city and its refugee camp and began searching from house to house after dark tonight.

Dozens of Palestinians were arrested in the searches, including residents with no connections to militant groups, witnesses said. The army said soldiers arrested 30 suspects including a bomber on the way to an attack and two relatives of one of the two teenage suicide bombers who carried out an attack on a bus last Monday that killed 14 people.

In the Gaza Strip, a 13-year-old Palestinian boy was killed in the Rafah refugee camp when soldiers shot at Palestinians throwing stones and firebombs, local residents said. The army said there were heavy exchanges of fire in the area and the boy may have been hit by Palestinian fire.

Two more Palestinians were injured after dark in Rafah, when troops shot as about 15 tanks and two bulldozers moved into the camp and began demolishing structures not far from the border with Egypt, residents said.

Meanwhile, Assistant Secretary of State William J. Burns wrapped up a visit during which he presented the Israelis and Palestinians with the peace plan that calls for a provisional Palestinian state by the end of 2003 and full independence by 2005.

But Israel complained that the proposal did not fully address its security concerns, while Palestinians said the plan's omission of presidential elections was an effort to sideline Palestinian leader Yasser Arafat.

Arafat has said he is still studying the plan and Israeli Prime Minister Ariel Sharon is scheduled to respond within a week.

Burns will take the comments back to the "quartet" -- the United States, United Nations, European Union, and Russia -- which is to adopt the final plan by December.

The U.S. snub of Arafat was clear in Burns' visit -- the envoy met with a Palestinian legislator at her home just a few yards from Arafat's office in the West Bank city of Ramallah. The United States has criticized Arafat for not taking a firmer hand against anti-Israeli militants and has also pressed for political and economic reform in the Palestinian Authority.

In explaining Israel's operation in Jenin, Israeli Defense Minister Binyamin Ben-Eliezer called the city a "capital of terror" and said troops would "clean up" the town. Arafat called the incursion a "crime."

Near Jenin today, troops arrested an activist of the militant group Hamas, Mahmud Abadi, who was on his way to carry out a suicide bombing in Israel, the army said.

The Israeli operation in Jenin will continue for a week or longer, Israeli television reported. Israeli troops have been in most West Bank towns since June as part of an operation that began after a series of suicide bombings.

Israeli troops pulled back to the outskirts of Jenin on Oct. 18, but the suicide attack in Northern Israel came three days later, and Israel said the bombers were from the Jenin area.

In addition to those in Jenin, about 15 Palestinians were arrested in the West Bank over the weekend, the army said.

Overnight in the West Bank city of Nablus, members of the al-Aqsa Martyrs Brigade, a militia linked to Arafat's Fatah movement, dragged two sisters from their home and shot them both in their legs, claiming they collaborated with Israel's intelligence services.

One of the women, Haifa Rihan, a 39-year-old divorced mother of six, died afterward, an al-Aqsa member said on condition of anonymity.