Israelis enter another West Bank town

An Israeli soldier scans buildings for snipers in Tulkarem.

JERUSALEM (CNN) -- Israeli forces entered the West Bank town of Qalqilya on Sunday in what Israel said was an operation to stamp out terrorist activity.

The Israel Defense Forces said "regular and reserve" troops were executing searches and arrests and a curfew had been imposed in Qalqilya.

Similar military operations were executed Saturday in two other West Bank towns -- Bethlehem and Tulkarem. Israeli troops continued to operate in and around Tulkarem at midday Sunday but had withdrawn from Bethlehem.

An Israeli soldier was killed and two others were wounded Saturday in Tulkarem, the IDF said. The IDF said Palestinians opened fire on the soldiers during the operation. The two wounded soldiers were evacuated to a hospital.

Troops entered Tulkarem "in order to prevent terror activity emanating from the city," the IDF said in a statement.

Palestinian security sources said Saturday night that Israeli troops, backed by about 20 tanks and several helicopters, moved into Bethlehem from three directions.

Israeli troops fired shots in the air and used megaphones to announce a curfew, warning residents not to leave their homes, Palestinian sources said.

A few weeks ago, Israel completed its Operation Defensive Shield military action that came during a wave of suicide bombings by Palestinian militants aimed at Israeli citizens.

But the military has been carrying out continuing incursions into the West Bank -- operations Israel said are meant to thwart terror attacks and hunt down militants.

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In Gaza on Saturday, a 12-year-old Palestinian girl and her 40-year-old grandmother were killed by an Israeli tank shell in the Al Buraije Refugee Camp near Deir al Balah, the Palestine Red Crescent Society said. The IDF expressed "sorrow for the tragic incident."

Palestinian sources said the tank was positioned on the border with Israel. The two badly burned bodies were found in a field where they had been shepherding their flock, the sources said.

Israeli military sources said two people acting suspiciously approached to within about 50 yards of the border in Gaza.

Diplomatic mission

CIA Director George Tenet is headed back to the Middle East, perhaps before the end of the week, Secretary of State Colin Powell said Sunday.

Powell, speaking in an interview taped for CNN's "Late Edition," said William Burns, assistant secretary of state for Near Eastern Affairs, also will return this week to the region.

It was reported last week that a trip by Tenet was put off because of al Qaeda terrorist threats in the United States.

Security cooperation between Israel and the Palestinians and the rebuilding of the Palestinian security forces are among the topics that have been mentioned as being on Tenet's agenda.

Tenet proposed a cease-fire and security plan last June, urging Israeli and Palestinian security organizations to reaffirm commitments to agreements under the April 2001 Mitchell report.

The Mitchell report calls for a resumption of security cooperation, a halt to the construction of Jewish settlements in the Palestinian territories, a denunciation of terrorism and resumption of peace talks.