The Israeli military said Friday it would begin building a fence along parts of the West Bank to keep out attackers, while the new Palestinian security chief said he wants to "put an end" to militias involved in shooting and bombing attacks on Israelis.

Gen. Abdel Razak Yehiyeh, who was appointed interior minister in a weekend Palestinian Cabinet reshuffle, said he would first engage in dialogue with the armed groups. Yehiyeh did not say how he would proceed if his appeals go unheeded.

Israel's Defense Ministry, meanwhile, said it would begin construction of a 75-mile fence along one-third of the unmarked frontier with the West Bank on Sunday. The fence is designed to keep out Palestinian homicide bombers and gunmen who have killed more than 520 Israelis in the past 21 months of fighting. In the same period, more than 1,700 people have been killed on the Palestinian side.

There were signs of tension in Israel's coalition over the fence, which the Defense Ministry said would more or less run alongside the so-called Green Line -- Israel's border before the capture of the West Bank in the 1967 Mideast war.

Jewish settler leaders and right-wing parties in Prime Minister Ariel Sharon's coalition demanded that a fence instead be built around Palestinian towns and cities.

Settler leaders have met with five right-wing Cabinet ministers to enlist their support for blocking a fence that would run along the Green Line, the Haaretz daily reported. The chairman of the Settlers' Council, Benzi Lieberman, has said he will wage a "bitter struggle" against the government if the fence is built, the daily said.

About 200,000 Jewish settlers live in the West Bank, and settler leaders fear that what the Defense Ministry is describing as a "security fence" will turn into a future border with a Palestinian state and leave the settlers further isolated on the wrong side.

At least in some areas, however, the fence would cut deep into the West Bank. The army has already seized about 30 square miles of West Bank land near the Palestinian towns of Jenin and Tulkarem for the construction of the barriers.

The Palestinians have dismissed the fence construction as ineffective, saying only peace agreements can bring Israel security. "We don't want physical separation," Mohammed Dahlan, the former head of the Palestinian Preventive Security Service in Gaza, told the Yediot Ahronot daily. "This fence will be a fence of hatred. The `whites' in Tel Aviv and the `blacks' in the West Bank."

Yehiyeh, the Palestinian security chief, said Friday, a day after being sworn in, that he would strive to neutralize the armed groups that have been carrying out terror attacks. "We should put an end to all the militias. We should end it completely," Yehiyeh said in an interview with The Associated Press.

"I will not agree in any way to pollute the name of the Palestinian people with terrorism," Yehiyeh said.

The attacks have been carried out by the military wings of the various Palestinian factions, including the Al Aqsa Martyrs' Brigade, which is linked to Arafat's Fatah movement. Israel has accused Arafat of doing little to stop the attacks or even encouraging and financing them, a charge he has denied.

Yehiyeh did not say how he would handle the militias, and it was not immediately clear how much authority he was being given by Yasser Arafat.

Critics of Arafat's reform program have said the changes are largely cosmetic, and the Palestinian leader is keeping power concentrated in his hands.

In the reshuffle, Arafat reduced the size of the Cabinet from 31 to 21 ministers, adding five new members, but keeping in place several who have been accused of engaging in corruption.

Several Palestinian legislators complained that ministers accused of mismanagement were not ousted. They demanded that the entire Cabinet be presented to the parliament for approval. However, Arafat said he would only submit the appointment of the five new Cabinet members to the legislature next week.

Also Friday, Israeli forces entered the West Bank city of Hebron before dawn. Israeli armored vehicles and a bulldozer surrounded an empty building, arrested a Hamas activist and then destroyed the structure, leaving after about two hours.

The Israeli military said three suspects were arrested, and an explosives laboratory was found in the building and destroyed.

At the Jewish settlement of Kadoumim, near Nablus, a Palestinian stabbed and lightly wounded an Israeli. Soldiers shot and killed the attacker, the military said.

The military said Shin Bet agents found a huge bomb near the West Bank town of Qalqiliya and exploded it safely. In a statement, Sharon's office said the bomb, made up of "dozens of kilograms (pounds) of explosives," was meant to be planted in Israel. Qalqiliya is next to the unmarked line between the West Bank and Israel.

Israeli Foreign Minister Shimon Peres, meanwhile, said he has resumed contacts with Palestinian officials but has no plans now to talk to Arafat, who accused Israel of trying to derail his attempt to reform the Palestinian leadership.

Peres told Israel Radio that his talks with Palestinians are "just initial probes, and that's why I'm being so careful not to go into detail, because there aren't any details yet."

Sharon has ruled out peace negotiations with the Palestinians until all violence stops and has banned talks with Arafat, charging that he is responsible for Palestinian attacks. However, Peres said Sharon had set no limits on his current contacts. "I don't know about any conditions, but I don't plan on talking to (Arafat) at this point, anyway," he said.

Several months ago, Peres and Palestinian negotiator Ahmed Qureia came close to agreement on a Mideast peace plan under which Israel would recognize a Palestinian state before solutions were negotiated on key issues such as borders and Palestinian refugees.

Peres said the concept was similar to the idea of a provisional state for the Palestinians, raised this week by Secretary of State Colin Powell.