Jerusalem ? Israel locked down the West Bank and Gaza Strip on Sunday ahead of its national election, after a large-scale military incursion into Gaza and warnings that Palestinians may try to disrupt the voting with violence .

About 26,500 police and soldiers were deploying to guard against Palestinian attacks during the voting Tuesday, police spokesman Gil Kleiman said. There were general warnings of attacks by Palestinians over the next 48 hours, but no more than usual, he said.

However, Israeli Defense Minister Shaul Mofaz told Israel’s Cabinet on Sunday that Israel was in the midst of an “assault of terror,” both in terms of the scope of warnings and attempts to carry out attacks.

Wrapping up his campaign in Haifa, the home of his main opponent, Prime Minister Ariel Sharon said he would try to set up a broad-based government after the election.

On Sunday afternoon, Israel imposed a blanket closure on the West Bank and Gaza Strip, barring all Palestinians from entering Israel and confining most to their communities. Israel has enforced stringent travel bans on Palestinians since the outbreak of fighting, but Sunday’s restrictions, to be in effect until Wednesday, impeded movement even further.

The military said the Allenby Bridge between Jordan and the West Bank and the Rafah crossing between Gaza and Egypt would remain open.

Palestinians drew a connection between the Israeli election and a large-scale Israeli incursion into Gaza City early Sunday in which 12 Palestinian gunmen were killed and 67 wounded. Palestinian Information Minister Yasser Abed Rabbo said it was part of Sharon’s re-election campaign.

In Cairo, where the Egyptian government has been trying to forge an agreement among Palestinian factions for an end to attacks against Israeli civilians, the Arab League issued a statement condemning the Israeli incursion and warning that failure of the international community to stop such actions “would increase the feelings of Arab anger and frustration.”

U.N. Secretary-General Kofi Annan issued a statement deploring the “ominous” escalating violence, criticizing Israeli operations “that place Palestinian civilians in harm’s way” and Palestinian rocket attacks on Israeli civilians.