Israeli troops entered the West Bank city of Nablus Friday, hours after an attack by a Palestinian gunmen on a nearby Jewish settlement that killed five people.
Palestinian witnesses say dozens of Israeli tanks and armed bulldozers poured into Nablus from four directions. Sporadic bursts of machine-gun fire from the tanks have been reported but no resistance was evident as soldiers used loudspeakers to declare a curfew.
Nablus is a short distance from the Jewish settlement of Itamar, where a Palestinian gunman attacked a home, killing five people. The victims include a mother, three of her children and a security guard at the settlement.
Israeli forces stormed the house, killing the Palestinian attacker and conducting searches in the area, after residents said that a second gunman had been sighted.
The incident is one of a series of Palestinian attacks, including two suicide bombings in recent days, which have claimed the lives of at least 26 Israelis. In response to the violence, Israel is expanding its military operations in the West Bank.
The Israeli Army has begun a limited call-up of several thousand reservists but on other reserve units have been placed on high alert and their commanders have also been warned that they might be asked to serve at short notice.
Israeli Prime Minister, Ariel Sharon will convene his security cabinet today to discuss further military actions. Raanan Gissin, a spokesman for Mr. Sharon, described the attack against Itamar as "horrendous" and said Israel must respond.