Updated

Thousands of Palestinians marched through Gaza City on Thursday at the funeral procession of a cameraman killed while covering a day of fighting that killed 20 Palestinians and three Israeli soldiers.

Three Gaza militants who tried to carry out a new attack on a border crossing were stopped by Israeli troops, the army said. One attacker was killed, another was wounded and a third fled the scene, the army said. Kerem Shalom, a crossing used to deliver humanitarian supplies to Gaza, was closed after the attack.

Israel has limited the flow of goods into Gaza since the Hamas militant group seized control of the area last June, and tightened the blockade in recent weeks following intensified rocket attacks from Gaza.

Israeli troops surrounded a militant hideout in the town of Qabatiya early Thursday, and exchanged fire for about an hour with two Islamic Jihad militants inside, before shooting them dead, Israeli officials said.

Abu Ahmad, an Islamic Jihad spokesman, vowed swift retribution.

"You will not escape the coming revenge," he said.

Fadel Shana, a 23-year-old cameraman with the Reuters news agency, was struck, along with two bystanders, as he filmed Israeli tank movements in the distance during the bloodiest day in Gaza in more than a month.

Shana's body was wrapped in a bloodied Palestinian flag as fellow journalists marched alongside carrying his broken camera and bloodstained flak jacket. The marchers waved Palestinian flags and carried small posters of Shana posing with his camera. "Fadal Shana, goodbye, the victim of the truth," the posters said.

Later, the body was taken to Shana's hometown of Khan Younis in southern Gaza. About 3,000 Palestinians attended the funeral.

"Fadel, Fadel, loved by God!" the crowd chanted.

Young Palestinian men wailed in grief, and a woman on a balcony screamed and banged her hands on the railing. Gunmen fired into the air, and flags from the rival Fatah, Hamas and Islamic Jihad movements were seen.

Reuters released the final video taken by Shana in the seconds before his death. The footage shows a tank on a distant hilltop opening fire. A tank shell is seen flying toward the camera followed by a large explosion before the screen goes black.

Pictures taken by colleagues after the attack showed his jeep on fire and Shana's body lying next to it along with several other bodies strewn along the road. Shana's jeep was marked "Press" and witnesses said the cameraman was wearing an identifying flak jacket.

Shana was killed near the Bureij refugee camp in central Gaza. He had been in the area to film the aftermath of a deadly Israeli airstrike that killed 12 Palestinians, including five children aged 12-15, according to medical officials.

The Palestinian Journalists Union declared a one-day strike to protest Shana's death. The Foreign Press Association, representing journalists in Israel and the Palestinian territories, expressed "profound sadness."

"His death is a stark reminder of the risks our Palestinian colleagues take every day to cover the news in Gaza," the FPA said.

Hassan Kashef, a prominent Gaza journalist, accused Israel of targeting Shana. "Israel fears the truth. And they want to kill the truth," he said. "And Fadel was killed while his camera was showing the truth."

The Israeli military said it expressed "sorrow" for his death but did not accept responsibility, saying only it was investigating.

Despite near daily Israeli-Palestinian violence, casualties among journalists are very rare. Only three others have been killed covering the West Bank and Gaza Strip since 1992, according to the New York-based Committee to Protect Journalists.

Wednesday's death toll, which included the killing of three Israeli soldiers in a Hamas ambush, was the highest since a broad Israeli military offensive that ended in early March killed more than 120 Gazans, including dozens of civilians, over several days. Israel carried out the offensive in response to heavy rocket barrages on southern Israeli towns launched by the ruling Hamas militant group.

Since then, Israel and Hamas had appeared to be honoring an informal truce despites sporadic violence.

The latest violence started on Tuesday night with an army operation in northern Gaza aimed at keeping suspected militants away from the border fence, the Israeli military said. During the ensuing clashes, the military said in a statement, Palestinian gunmen opened fire at Israeli soldiers from within a mosque used for storing explosives. One soldier and several Palestinian militants were wounded.

As that operation wound up in the morning, Palestinian militants ambushed an Israeli ground force in northern Gaza, killing three soldiers, the military said. The soldiers entered Gaza in pursuit of two Hamas militants who planted a bomb near the border and were ambushed by another Hamas force, Israeli defense officials said.

Other troops went in to the area and came under mortar fire from militants. The army said it responded with an airstrike and identified hitting militants in the Bureij area.

Palestinian President Mahmoud Abbas condemned the "Israeli aggression in Gaza" and urged all sides to "cooperate with Egyptian efforts."

He appealed Thursday for greater urgency in reaching peace in the Middle East, saying a conference planned for Moscow in June must "save the peace process."

Israeli Foreign Ministry spokesman Arye Mekel said Jerusalem has not yet decided whether it will participate in the conference.

Palestinian Foreign Minister Riad al-Malki said peace talks with Israel are showing no progress, and Abbas will ask for "clear, solid" American intervention when he meets with PresidentBush in Washington next week.