GAZA CITY -- Some 5,000 supporters of the Islamic group Hamas demonstrated Friday in the streets of Gaza City, promising to avenge Israel's killing of their leader, Salah Shehade, and swearing loyalty to his successor.

"This demonstration pledges allegiance to the new chief of the Qassam brigades," senior Hamas leader Abdel Aziz al-Rantissi told the crowd, without giving the name of Salah's replacement as commander of the Ezzedine al-Qassam brigades.

"Our resistance and jihad (holy war) will continue until the end of Israeli occupation and all our people and groups will avenge the blood of our martyrs and the assassination of Sheikh Salah Shehade," Rantissi said.

"Our response will be like an earthquake," he added, four days after an Israeli F-16 dropped a one-ton guided bomb on Shehade's house, also killing his bodyguard, wife and daughter, as well as 11 other civilians, including nine children.

Some supporters of the group, which has claimed the bulk of anti-Israeli attacks since the start of the Intifada in September 2000, shouted through loudspeakers that the movement's armed wing, would carry out martyrdom-seeking operations "everywhere in Israel".

Separately, Rantissi told AFP the Palestinian police and security forces had arrested in Gaza City a handful of men suspected of assisting Israel's air strike.

"These people have been questioned to discover if they whether had any link to the assassination," the Hamas leader said.

However, the police would not comment on whether they had detained anyone.