Updated

A Palestinian bomber blew himself up Monday at a busy crossroads in northern Israel. He killed only himself, but the second suicide attack in as many days demonstrated attackers still have the means and the will to strike despite Israel's military offensive across the West Bank.

Also, Israeli officials disclosed that a Palestinian plan to detonate a one-ton bomb in the parking lot beneath twin 50-story towers in Tel Aviv was thwarted three weeks ago. Troops raided a West Bank town, preventing the planned car bombing, according to an Israeli military officer and a government official. Last year, Israel arrested two Palestinians who had also planned to bomb the towers.

The officer, appearing at parliament's Foreign Affairs and Defense Committee, said Palestinian militants were trying to rebuild their infrastructure for bombing attacks. The officer and the government official, who was contacted by The Associated Press, both spoke on condition of anonymity.

Also Monday, Israeli troops entered the West Bank town of Tulkarem and arrested a woman who planned to carry out a suicide bombing, Israeli security sources said. Palestinian officials identified her as Thawriyeh Hamamreh, 24, from the village of Jaba near Jenin.

Meanwhile, Prime Minister Ariel Sharon ordered the dismissal of Cabinet ministers from two ultra-Orthodox parties, setting off a political crisis that could threaten his government.

Sharon made his decision after the two parties failed to support the government on an emergency economic plan. However, the dismissals would not take effect immediately, leaving time for last-minute wheeling and dealing.

The military sweep in the West Bank, launched March 29 amid the deadliest wave of suicide bombings ever faced by Israel, resulted in the killing or capture of hundreds of suspected militants and a sharp drop in the number of attacks.

The relative calm inside Israel in recent weeks suggested the Israeli raids had seriously disrupted the network of attackers, who come from several different Palestinian groups, or that the militants had scaled back their bombings, at least temporarily.

Until Sunday, Palestinian militants had carried out only one suicide attack that killed Israelis in the past five weeks — a May 7 bombing that killed 15 in a pool hall near Tel Aviv.

But a bomber disguised in an olive drab army uniform entered a fruit and vegetable market Sunday and set off his explosives, killing three Israelis and wounding dozens in Netanya, a coastal city that has been hit repeatedly by militants.

Then Monday morning a bomber struck at the Taanakhim Junction, a few miles inside Israel near the northern West Bank. An Israeli driver notified authorities when a man waiting at a bus stop aroused suspicion. When the patrol asked the Palestinian for identification, he blew himself up, police said. No one else was hurt.

No group claimed responsibility for Monday's blast, while the Popular Front for the Liberation of Palestine, a radical PLO faction, said it carried out Sunday's attack and identified the bomber as 18-year-old Osama Boshkar from the West Bank's Askar refugee camp.

The group is headed by Ahmed Saadat, who is detained in a Palestinian jail in the West Bank town of Jericho under British and U.S. supervision. Israel demanded the detention of Saadat, whose group carried out the killing of Israel's tourism minister last October.

An Israeli government spokesman, Danny Shek, said Saadat "might have been instrumental in commanding and masterminding the bombing." However, Deputy Defense Minister Dalia Rabin Pelossof said there was no conclusive proof that Saadat ordered Sunday's attack.

Saadat has given a telephone interview from detention, and Israeli media reports said he has received visits from Palestinian activists. The British Embassy in Tel Aviv said it has asked Israel to document the allegations against Saadat.

The prospect for peace negotiations remained dim after breaking down more than a year ago. Israeli Prime Minister Ariel Sharon says the violence must stop before they can resume and that he does not view Palestinian leader Yasser Arafat as a negotiating partner.

In another development, Palestinians say they are now required to obtain Israeli permits to travel from one Palestinian city to another, institutionalizing tough travel restrictions in place throughout the 20 months of Mideast fighting.

In a meeting with foreign diplomats Monday, Arafat said the Israelis had effectively divided the West Bank into eight separate cantons.

Ofir Haham, spokesman for the Israeli department responsible for the Palestinian territories, confirmed that Palestinians traveling from one West Bank area to another needed to apply to Israel for permits and said the policy began several months ago. However, Haham denied Israel had divided the West Bank into Cantons.

Also, Israel's Housing Ministry is asking for bids to build almost 1,000 apartments in the West Bank at existing Jewish settlements.

The United States and European countries have sharply criticized Israel's settlement policy in the West Bank and Gaza Strip. Palestinians say the settlements are on Arab land and designed to prevent the creation of a Palestinian state.

More than 200,000 settlers live in about 150 settlements scattered across the West Bank and Gaza Strip, and Israel has said it needs to build in the settlements to account for "natural growth" of the population.