Israeli forces have moved back into the West Bank city of Nablus, engaging in gun battles with Palestinian militants and imposing a new curfew.
Israeli soldiers raided Nablus for the second time in two weeks as part of ongoing efforts aimed at arresting wanted Palestinian militants.
The troops moved into the ancient quarter, or Old City, of Nablus, where they ran into fierce resistance from Palestinian militants who opened fire on them. The soldiers returned fire.
Israel has imposed a military curfew on the city center, forcing about 40,000 people to stay in their homes and preventing children from going to school.
The latest raid occurred less than 24 hours after soldiers withdrew from the city, ending a two-week operation in which they arrested dozens of suspected Palestinian militants.
The Israeli army says the raids against Nablus will continue as long as, what it calls, the city's terrorist infrastructure remains intact.
The sweep has been one of the biggest by the Israeli army in recent months, reflecting a determination to capture militants in what Israel sees as the absence of any effort by the Palestinian Authority to confront armed Palestinian groups.
The Israeli army has also been operating with renewed vigor in the Gaza Strip.
In a two-day operation in the Rafah refugee camp last week, Israeli soldiers destroyed a tunnel that had been used to smuggle weapons into Gaza from neighboring Egypt.
At least nine Palestinians were killed in the raid during exchanges of gunfire between militants and the troops. A number of homes also were destroyed.
On Monday, Palestinian residents held demonstrations calling for an end to the Israeli military incursions and the destruction of their homes.
The unrelenting violence has frozen efforts to implement the so-called Roadmap plan to end the bloodshed and grant Palestinians full statehood by 2005.
To reach this goal, the plan calls for the dismantling and disarming of Palestinian groups responsible for more than three years of attacks against Israelis.