NABLUS, West Bank ? Israeli troops rolled Friday into a refugee camp on the edge of Nablus, rounding up hundreds of Palestinian men, imposing a curfew and blowing up the home of a suicide bomber.

Just a few miles from Nablus, a Palestinian gunman was shot dead after infiltrating a Jewish settlement.

An Israeli Army soldier leads Palestinian detainees into a vehicle for transport, on the first day of an Israeli military incursion in the West Bank city of Nablus. Dozens of tanks and armored vehicles early Friday swept into Nablus, closing down the most populous city in the West Bank.

The confrontations came as diplomats converged on the region, looking for ways to end, or at least reduce, 20 months of Mideast violence. But no new peace initiatives have emerged.

The almost daily Israeli forays into Palestinian territory, which once drew widespread international criticism, now produce little reaction, aside from Palestinian condemnations.

In his meeting with U.S. Assistant Secretary of State William Burns, Prime Minister Ariel Sharon cited the possibility of “progress” on the diplomatic front, although he quickly added conditions.

Sharon’s office quoted the prime minister as telling Burns of “Israel’s position that cessation of terror, violence and incitement and a thorough reform of the Palestinian Authority were conditions for progress.”

Sharon played host Friday to Burns and Osama el-Baz, adviser to Egyptian President Hosni Mubarak. CIA Director George Tenet was expected in the region this weekend.

The United States has proposed an international conference on the Mideast this summer, but no date has been set.

The Israeli troops entered Nablus and the adjacent Balata refugee camp in dozens of tanks and armored personnel carriers, saying the incursion was carried out “in the wake of recent murderous attacks.”

The camp is a stronghold of the Al Aqsa Martyrs Brigade, a militia that has carried out many deadly attacks.

Arafat denounced the incursion, saying, “this is Israel’s message to the whole world, and proof they do not want to reach any agreement.”