Palestinian militant group Hamas said on Wednesday it had the right to target PM Ariel Sharon to avenge the killing of its leader but reassured the US it was not in the firing line. Amplifying the mood of a spiralling conflict, Abdel-Aziz al-Rantissi, the Islamic group’s hardline replacement for Yassin in Gaza, urged attacks on Israelis everywhere — a call Hamas officials later said was limited to Israel and the Palestinian territories.Israel has vowed to take out Rantissi and other militants. Ignoring condemnation, it says it is defending itself against suicide bombers that have killed hundreds of Israelis.Exiled Hamas leader Khaled Meshaal was quoted as telling pan-Arab Al-Hayat daily in Damascus that Hamas now had the right to ‘‘hunt down the big Zionist heads’’ including Sharon. But he added that any decision would depend on Hamas’s military wing.Al Aqsa Martyrs Brigades, an armed faction of Palestinian President Yasser Arafat’s Fatah movement, also said Israeli leaders would not be immune.‘‘Wherever you find a Zionist kill him,’’ a masked al Aqsa leader said, repeating an order issued to the group’s members. Sharon’s office had no immediate comment.Security around Israeli leaders has been beefed up to levels not seen since just after the killing of Tourism Minister Rehavam Zeevi in 2001 by gunmen from the Popular Front for Liberation of Palestine. Arafat, who has declared three days of mourning for Yassin, appealed for calm. ‘‘I am against any attacks on civilians, on Israeli and Palestinian civilians,’’ he said. Keeping tensions high in Gaza, 10 tanks rolled into the Khan Younis refugee camp and bulldozers razed several homes near a Jewish settlement. About 60 families fled, witnesses said. Troops destroyed abandoned buildings used by militants for firing rockets. — (Reuters)