Top Hamas leader Ibrahim al- Maqadma and three of his aides were killed when a rocket fired by an Israeli helicopter struck their car in the Gaza Strip.
The killing drew an immediate response from Hamas. Its spokesman, Abdel-Azziz al-Rantizi, said the 'assassination will launch a new stage of war against the Jews.' He said all Israeli leaders will be open targets for Hamas. Angry Hamas supporters gathered in the streets outside the Gaza City hospital where the dead were taken.
The Palestinian Authority said the attack was an attempt to undermine it at a time when Palestinian leaders were meeting to discuss important political reforms. Cabinet minister Saeb Erekat said the Palestinian Authority holds Israel responsible for the consequences of the attack.
Members of the Palestinian Central Committee are in the West Bank town of Ramallah considering several proposals, including the nomination of Mahmoud Abbas to be the Palestinians Authority's first prime minister. Palestinian leader Yasser Arafat agreed to appoint a prime minister after pressure from the international community, which has been pushing for political reform.
Hours before the Gaza killing, Palestinian gunmen disguised as religious Jews killed two Israelis in a raid on the West Bank Jewish settlement of Kiryat Arba near the town of Hebron. Hamas claimed responsibility for that attack; saying it was revenge for the dozens of Palestinians killed by the Israeli military during operations this week in the Gaza Strip. The two attackers were killed by security forces.
In a separate incident, two other armed Palestinians were reported shot dead in the Jewish settlement of Nehugot, just south of Hebron.
Israeli troops stepped up operations in Gaza following a suicide bombing that killed 15 people and wounded dozens more Wednesday in the northern Israeli city of Haifa.