GAZA CITY – The Hamas movement has said that "all options are open" to avenge the killing of 17 Palestinians, including five children, during clashes with Israeli troops.
The warning on Thursday came as thousands of residents of the Gaza Strip gathered for the funeral procession of a cameraman who was killed as he covered the fighting.
In a statement published on the internet, the armed wing of Hamas called on its fighters to attack Israel "in every place and with all means available".
"This enemy only understands the language of force," it said.
Three Israeli soldiers were also killed before the military withdrew from the Gaza Strip late on Wednesday.
Ehud Olmert, Israel’s prime minister, said that Hamas was "responsible" for the violence.
"We consider that Hamas bears sole, direct responsibility for what happened in Gaza and it will pay the price," he said in an interview with Israel’s Maariv newspaper.
"There is a war in Gaza and we will act against terrorism. Last year we killed more than 200 terrorists."
The surge in violence came after a relatively quiet month and threatened to unravel an Egyptian effort to mediate a ceasefire between Israel and Hamas.
The body of Fadl Shanaa, who worked for the Reuters news agency, was wrapped in a bloodied Palestinian flag on Thursday, as fellow journalists marched alongside carrying his broken camera and bloodstained flak jacket.
He was killed with two Palestinian civilians when a missile hit his vehicle on Wednesday.
The marchers waved Palestinian flags and carried posters of Shanaa posing with his camera.
‘Victim of Truth’
"Fadl Shanaa, goodbye, the victim of the truth," the posters said.
Later, the body was taken to Shanaa’s hometown of Khan Yunis in southern Gaza where about 3,000 Palestinians attended the funeral.
Shanaa had been travelling to the al-Bureij camp to cover the aftermath of an air raid that killed at least 12 Palestinians, including five children aged between 12 and 15.
An Israeli helicopter had fired four missiles at targets near the camp in central Gaza.
Alastair Macdonald, Reuters bureau chief for Israel and the Palestinian territories, said the company wanted an explanation from the Israeli army for Shanaa’s death.
"We are asking the army to explain if they aimed at the position where Fadel was and if so, why they did that," he said.
"Our objective is to protect our journalists and to ensure that such tragic events are not repeated."
The Palestinian Journalists Union declared a one-day strike to protest against the killing of Shanaa.
"His death is a stark reminder of the risks our Palestinian colleagues take every day to cover the news in Gaza," the Foreign Press Association, representing journalists in Israel and the Palestinian territories, said.
Reuters released the video taken by Shanaa in the seconds before his death.
The footage shows a tank on a distant hilltop open fire. A tank shell is seen flying toward the camera followed by a large explosion before the screen goes black.
Pictures taken by his colleagues after the attack showed that the vehicle was clearly marked as a media vehicle.
Major Avital Leibowitz, an Israeli military spokeswoman, told Al Jazeera that the army had "no intention whatsoever" of targeting journalists.
"You have to take into consideration, when we’re talking about a war zone, when there is an exchange of fire and journalists are hanging around in those places … sometimes a journalist will be hit," Israeli military spokeswoman, said.
She said the incident was being investigated, but it was possible that the signs on the vehicle may not have been visible to the soldiers in the tank.
Security Stepped up
Security has been stepped up across Israel for the week-long Jewish Passover holiday beginning on Saturday, with restrictions on the occupied West Bank tightened and police reinforcements deployed throughout the country.
"Over the next ten days thousands of policemen will be deployed in the whole country in all sorts of places, streets and commercial centres," Micky Rosenfeld, Israeli police spokesman, told the AFP news agency.
"There is no concrete threat for the holidays, but the usual threats that we are used to."
Meanwhile on Thursday, two Islamic Jihad fighters died during an exchange of fire with Israeli troops during an incursion in the West Bank town of Qabatiya.
Islamic Jihad said that the men killed were Bilal Komel, a commander long-wanted by Israel, and 19-year-old Ayed Zakarna.
(Aljazeera and agencies)