NABLUS, West Bank, 26 May — Israel pressed ahead yesterday with its policy of raids in autonomous Palestinian areas, leaving a woman and her 12-year-old niece dead in the Gaza Strip and sweeping the West Bank town of Tulkarm for Palestinian activists after a series of bomb attacks earlier in the week.

A woman and her niece were mortally wounded by Israeli fire when an army unit, backed by tanks, entered the El-Boureij refugee camp in the central Gaza Strip, Palestinian security sources said. They later died from their injuries.

Israeli tanks and troops stormed back into Bethlehem and shooting erupted last night, two weeks after the army lifted a siege of Palestinian fighters trapped inside its Nativity church, witnesses said.

Military sources confirmed Israeli “activity” inside the West Bank city holy to Christians worldwide but gave no further information.

Palestinian witnesses said Israeli jeeps followed by tanks and armored personnel carriers entered Bethlehem and fanned out through the city of 40,000 people after nightfall. They said shooting broke out and two explosions shook the ancient part of the town as Israeli helicopter gunships clattered overhead. No return fire from Palestinians was seen, they said.

Witnesses said Israeli troops had announced a curfew via loudspeakers and were ordering inhabitants to stay inside. Palestinian police said Israeli troops were searching houses within 200 meters (660 feet) of Manger Square.

In the West Bank, Israel detained about 100 Palestinians in its incursion into Tulkarm. The soldiers withdrew to the outskirts of Tulkarm in the afternoon but the army later imposed a curfew on the town.

The troops had been hunting Palestinian activists in Tulkarm, with one soldier shot and killed and two others wounded, one seriously, since soldiers poured into the area Friday.