A Palestinian suicide bombing in Gaza and an Israeli security alert that clogged the approaches to Tel Aviv airport for hours have underlined the failure of a US-brokered ceasefire to calm nine months of violence.
Hamas has promised to send 10 suicide bombers against Israel to avenge the killing of an 11-year-old boy in Gaza on Sunday.
In the West Bank, a roadside bomb explosion killed a 22-year-old Israeli army captain as his jeep passed near the flashpoint city of Hebron. The Popular Front for the Liberation of Palestine claimed responsibility.
A major security operaton halted traffic near Ben Gurion Airport near tel Aviv, after information that Palestinian militants were planning a bombing there.
Earlier on Monday, local time, a Palestinian suicide bomber died in an explosion, but caused no other casualties, at the Kissufim crossing between Gaza and Israel.
The United States criticised the two sides for the fresh bloodshed and State Department spokesman Richard Boucher told a news briefing: "We're deeply troubled over the upsurge... in violence over the weekend."
Adding to Israeli-Palestinian tensions, Israeli wrecking crews escorted by hundreds of paramilitary border police demolished 14 houses in the Shuafat refugee camp in Arab East Jerusalem. Israel says they were built illegally.
"We have urged the Israelis on numerous occasions to desist from the demolitions of Palestinian homes," a State Department official said, referring to such action as "provocative."
Israeli Foreign Minister Shimon Peres, who usually takes a more upbeat view than his senior partner in the governing coalition, Prime Minister Ariel Sharon, spoke of renewed efforts by Palestinian President Yasser Arafat to prop up the truce.
"The Palestinians told the Americans and us that on Saturday night there was a meeting held by Arafat where they decided to take very serious steps to calm things in the field," Peres said in broadcast remarks.
Peres, speaking to members of his Labour Party, said the moves would include arrests of Islamic militants by the Palestinian Authority. Palestinian officials were unavailable for comment on the Peres remarks.
But in Ankara, Israeli Defence Minister Binyamin Ben-Eliezer said Arafat could stop violence by simply raising his finger.
"If Yasser Arafat would like to stop it (violence)... he only has to do that," the minister told a news conference, holding up a finger. "It will take one day, two days and the silence will take over. Then we can sit and talk."
At least 477 Palestinians, 122 Israelis and 13 Israeli Arabs have been killed since a Palestinian uprising against Israeli occupation in the West Bank and Gaza Strip erupted in late September after peace talks stalled.
Hamas vows to send more bombers
The military wing of the Islamic group Hamas identified the bearded bomber as Nafez al-Nether and published his photograph in a statement saying its attack was "responding to the assassination and the killing of children".
Hamas has promised to send 10 suicide bombers against Israel to avenge the Israeli army killing of 11-year-old Khalil Mughrabi in Gaza on Saturday, local time.
Sharon expressed sorrow "over the boy's tragic death" in a statement, adding the circumstances of the killing were under investigation by the army, but firmly putting the blame for civilian casualties on the Palestinians.
"The continued terror, violence and incitement (by Palestinians) are behind the needless suffering and victims among innocent civilians," Sharon said.
Palestinian security officials said they detained a suspected Hamas member who was in a car behind the suicide bomber's van and who allegedly detonated the bomb with a cellular phone.
Israeli government secretary Gideon Saar said the Palestinian Authority did nothing to prevent the attack despite advance Israeli intelligence about the identity of the person, organisation and place of attack.
Palestinian hospital officials said an 11-year-old boy was wounded in the leg near the Gaza-Egypt border by Israeli gunfire on Monday. The army had no information on the incident, but reported three mortar bombs fired at Jewish settlements in Gaza and exchanges of gunfire in the West Bank, with no injuries.
Passengers trek to airport
Israel's security jitters were evident in the long lines of stopped cars and frustrated, baggage-toting airline passengers who opted to trek along the road in the stifling summer heat towards Ben-Gurion International Airport near Tel Aviv.
A police spokeswoman said security checks were stepped up at airport entrances off the Tel Aviv-Jerusalem highway after information that Palestinian militants planned a bombing there. Israel Radio said police were warned of a car bomb.
The Israel Airports Authority advised passengers to arrive at the terminal at least four hours before their flights to make time for extra security procedures.
Although tourism has dropped sharply since the start of the Palestinian uprising, Israelis have been flocking to Ben-Gurion in recent weeks to fly abroad for summer holidays.
Eighteen Palestinians, including the suicide bomber, and 10 Israelis have been killed since a ceasefire drawn up by US CIA Director George Tenet was to have taken effect on June 13.
In a pre-recorded videotape before Monday's Gaza blast, suicide bomber Nether quoted from the Islamic holy book, the Koran, and said: "I give it as a gift to the families of the martyrs and to those of the detainees in Zionist prisons."