Gunmen fired shots into the air and angry mourners cried for revenge as some 100,000 Palestinians marched in a furious procession to bury Abu Shanab, who was killed on Thursday by an Israeli rocket attack.
"Abu Shanab rest in peace. Our armies will go forward. We are the men of the dark night," a loudspeaker blared as his body, covered in a green Hamas flag, was carried aloft.
Shanab is to be buried in the Martyrs' Cemetery in the north of Gaza city.
But outraged Palestinians insisted Shanab was not being buried alone.
"The road map is being buried, only martyrdom operations will remain," a Hamas fighter said.
"The road map is being buried, only martyrdom operations will remain"
His pronouncement carried weight, as only hours earlier two of the most prominent Palestinian resistance groups formally ended their unilateral truce and vowed to renew their attacks on Israel.
Leaders of the Islamic Jihad and Hamas blamed the Israeli Prime Minister Ariel Sharon for the escalating tensions and threatened to retaliate by stepping up resistance attacks.
"We announce together today that Sharon assassinated the truce and delivered the final blow in killing political leader Ismail Abu Shanab," a joint statement of the Islamic Jihad and the Hamas said.
Calling off the ceasefire in retaliation to the assassination of Shanab, senior Hamas leader Abd al-Aziz al-Rantissi said the crime would invite a grave punishment.
"The streets of Tel Aviv, Haifa and Jerusalem will be filled with blood and Sharon will be responsible for it," Rantissi insisted.
Reporting from Gaza, Aljazeera's correspondent said the Israelis had set up a new checkpoint near Abu Holi in the centre of the Gaza Strip to prevent Palestinians from attending the funeral.
Al-Aqsa fighter killed
Elsewhere, Israeli forces shot and killed a Palestinian guerrilla and wounded two others when they opened fire on a hospital in the West Bank city of Nablus on Friday, hospital officials and witnesses said.
Witnesses said the three men being sought by Israel were sheltering in a small rooftop room of the Rafidya hospital. Soldiers shot the three men when they ventured out onto the roof, the sources said.
Khalid Namrudi, 32, was killed on the spot and his two fellow activists from an offshoot of Palestinian President Yasir Arafat's Fatah movement were in critical condition, the sources said.
"In the framework of our activities against the terrorist infrastructure in and around Nablus, Israeli forces operated in the area of Rafidiya hospital," military sources said.
"During the operation, a number of wanted men from al-Aqsa were spotted on the roof and the troops opened direct fire," the sources said.
Israeli forces entered Nablus shortly after a bus bombing in
Jerusalem on Tuesday to search for Palestinian fighters. On Thursday, they imposed a curfew on the city, one of the largest in the West Bank.
Attacks on Jenin
Earlier during Friday, heavy shooting broke out between Israeli troops and Palestinian resistance fighters in Jenin after a convoy of military tanks and jeeps attacked the northern West Bank town.
Palestinian security sources said at least 15 Israeli tanks and jeeps moved into the town on various sides, with troops firing flares as they went.
It was the second consecutive night of violence the people of Jenin had suffered at the hands of the Israeli army. Details of the full extent of the Israeli attack remained sketchy.
Israeli military sources confirmed an operation was underway in the town but would not give further details
In the Gaza Strip, Palestinian fighters fired mortars and rockets at Israeli settlements.
Meanwhile, Usama al-Bazz, political adviser to Egyptian President Hosni Mubarak held discussions in Ramallah with Yasir Arafat.
Al-Bazz is said to be carrying a letter for Arafat from Mubarak, Palestinian sources said.