Israeli troops have raided the West Bank town of Nablus, in an operation Palestinian officials say undermines the embattled government of President Mahmoud Abbas.
The Israeli military says soldiers searched homes for wanted militants and imposed a curfew. At least two Palestinians were arrested and five Israeli soldiers wounded in the operation.
Palestinian Prime Minister Salam Fayyad says Israel is trying to sabotage Palestinian efforts to improve security. He heads the emergency government Mr. Abbas created after the militant group Hamas seized Gaza earlier this month.
Israel has pledged to support the new government, but officials said Thursday they will continue to conduct operations against militants.
In another development, Israeli officials say they have allowed some food aid through Gaza's main commercial transit point, Karni. This is the first time Israel has opened the crossing since Hamas seized control of Gaza.
Also Thursday, former British Prime Minister Tony Blair says he will start his new job as special Middle East envoy immediately and will probably travel to the region next month.
On Wednesday, the international Middle East Quartet named Blair as its envoy to promote peace between Israel and the Palestinians. The Quartet includes the United Nations, the United States, the European Union and Russia.
The Quartet said recent events in the Gaza Strip and West Bank make it more urgent than ever to advance the search for peace in the Middle East.
Hamas seized control of Gaza in fighting with Mr. Abbas' Fatah faction earlier this month.
Hamas says it does not expect Mr. Blair to be impartial because he has previously supported American and Israeli positions.