Gaza, Mar 31: The Islamist group Hamas defended today a suicide bombing that killed four Israelis as ''resistance'' against Israeli ''crimes'', putting it at odds with Palestinian President Mahmoud Abbas, who condemned the attack.
Hours after the attack Israeli warplanes and artillery struck the Gaza Strip, though no casualties were reported.
A car explosion in Gaza later killed a top commander of the Popular Resistance Committees, a group behind many rocket attacks against Israel, Palestinian security sources said.
The group identified the commander as Khalil al-Quqa and accused Israel of being behind the explosion which killed him.
The Israeli army had no immediate comment.
The conflicting statements of Hamas and Abbas on the West Bank suicide bombing were the first since the president swore in the Palestinian Authority's first Hamas government on Wednesday.
Abbas has said he could overrule the group, which is sworn to Israel's destruction, if it continues to block peacemaking.
The suicide bombing, claimed by al-Aqsa Martyrs Brigades, occurred days after Israeli leader Ehud Olmert's Kadima party won elections on a platform of setting Israel's borders in the occupied West Bank unilaterally in the absence of peace talks.
Palestinians say such a move would annex land and deny them the viable state they seek in the West Bank and Gaza Strip.
Israeli officials said the bomber, whose group is part of Abbas's Fatah faction, was disguised as a religious Jewish hitchhiker and blew himself up when Israelis in a car picked him up near a settlement late yesterday.
A spokesman for Abbas told official Palestinian media that the president condemned the bombing and that he asked all factions to abide by a truce declared last year.
Hamas described the attack as a ''natural response to Israeli crimes''. Information Minister Youssef Rizqa said: ''Resistance is a legitimate right for people under occupation.''
The group is under pressure by Abbas, Washington and the European Union to stop violence, recognise Israel and abide by interim peace deals. Hamas carried out about 60 suicide bombings during an uprising that began in 2000, but has upheld the truce.
Palestinian governments under Fatah's control had condemned suicide bombings inside Israel, though used more careful language when it came to attacks inside the West Bank, which Israel captured in the 1967 W Asia war.
Prime Minister Ismail Haniyeh said in a column published on Friday in a British newspaper that ''we have every right to respond with all available means'' if Israel continues to launch attacks and to impose ''sanctions'' on Palestinians.
Haniyeh also ruled out any talk of his Hamas-led government recognising Israel or ending the fight against the Jewish state until Israel commits to withdrawing from Palestinian land.
Criticising Hamas for failing to soften its line since it won the election, the ''Quartet'' of West Asia mediators warned the group that direct financial aid to the Palestinian Authority would inevitably be affected.
Hamas, whose cabinet is set to meet for the first time on Tuesday, has dismissed such threats, saying it would opt to seek funding from other sources, such as the Arab world.
Israeli warplanes attacked Gaza after the bombing near a West Bank settlement, targeting more than a dozen sites the army said militants had used to fire rockets into the Jewish state.
Two Israelis died in one such attack last week.
Israeli forces also detained several suspected militants in the West Bank, a military source said. Israeli media quoted security sources as saying two men were involved in the suicide attack, one of them being the bomber's brother.
Israeli officials said Thursday's attack near the settlement of Kedumim followed dozens of warnings of impending attacks.
''The Palestinians continue to remain totally indifferent and are not preventing terror attacks,'' said David Baker, an official in the prime minister's office.