The new leader of the Palestinian militant group Hamas in the Gaza Strip, Mr Abdel-Aziz al-Rantissi, has pledged all out revenge on Israel for killing his predecessor Sheikh Ahmed Yassin.
Mr Rantissi and other Hamas officials, including overall leader Mr Khaled Meshaal, also stressed the militant group had no plans to take its fight beyond Israel and the Palestinian territories.
"The political leadership of Hamas has given a green light to the armed wing to act in the manner it decides," Mr Rantissi said in an interview at a hiding place.
"The door is open to react everywhere, at any time and by all means."
Mr Rantissi (56) was named to head Hamas in Gaza yesterday, making him the pivotal figure in the Islamic group bent on destroying Israel. He is widely seen as a hardliner even in a faction committed to a suicide bombing campaign against Israel.
Mr Meshaal, who lives in exile in Syria, was today quoted as saying Hamas now had the right to "hunt down the big Zionist heads" including that of Israeli Prime Minister Ariel Sharon in revenge for Yassin's killing.
But another senior Hamas official said the group had no intention of attacking US targets following Yassin's assassination.
"It's not in our policy to target Americans or American interests," Hamas political leader Mr Sayed Seyam said.
The US State Department had told Americans that Hamas had threatened revenge on US interests after Yassin's death, telling them to leave the Gaza Strip and also advising against travel to Israel or the West Bank.
Mr Rantissi dismissed Mr Sharon's evolving plan for pulling troops and settlers out of the Gaza Strip as no more than a "cover for committing more crimes against Palestinians."
"No one is betting on the peace process now. Is there anyone who thinks the Zionists will ever abandon Jerusalem...or dismantle settlements, release prisoners or return refugees?".
Marked for death by Israel, Mr Rantissi began his new duties of leader from underground with security around him beefed up. He survived an assassination attempt with minor injuries last June.
Keeping up pressure in Gaza, about 10 Israeli tanks backed by helicopter gunships rolled about 100 metres into Khan Younis refugee camp early on today and bulldozers razed several homes overlooking a Jewish settlement, witnesses said.
About 60 families fled their huts as the tanks laid down covering fire, witnesses said. There were no reports of clashes or casualties before the troops pulled back.
Israel pledged yesterday to keep targeting the leaders of Hamas and other Palestinian militant groups and said it would bring more security to the Jewish state.
Agencies