The US Middle East peace bid is in turmoil after a Palestinian suicide bomber killed 16 people on a Jerusalem bus, and Israeli helicopters killed ten Palestinians in strikes on Gaza.
Watching his "road map" peace plan engulfed in a new round of killing, President George W. Bush has condemned the Jerusalem bombing and called on "all the free world . . . to use every ounce of their power to prevent them".
But the militant Hamas group, which claimed responsibility for the Jerusalem blast, has promised more atttacks, and Israel has vowed to track down and kill more Palestinian militants.
Sixteen people were killed and more than 100 wounded when a Palestinian bomber disguised as an ultra-Orthodox Jew blew himself up on a bus in near Jerusalem's main open-air market during the afternoon rush hour.
Minutes later, Israeli helicopter gunships fired missiles at a car in Gaza City, killing two members of Hamas and five civilian bystanders. At around midnight, two more members of Hamas were killed in another helicopter missile attack.
Hamas said it sent the bomber to avenge Israel's attempt to assassinate Abdel-Aziz al-Rantissi, a co-founder of Hamas, in a missile attack in Gaza on Tuesday.
Israel officials claim the bomber behind yesterday's attack was dispatched before its attempt on Mr Rantissi and that 10 suicide bombers had been arrested by Israeli security forces since a US-brokered peace summit in Jordan last week.
Palestinian President Yasser Arafat condemned both the Jerusalem bombing and the Israeli missile strike on Gaza.
Israeli Prime Minister Ariel Sharon, undeterred by a rare rebuke from Mr Bush for the attempt on Mr Rantissi, vowed to pursue militants "to the fullest extent". But he also said Israel was deeply committed to moving forward towards peace.