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.
In the day's deadliest attack, an Israeli helicopter fired four missiles at targets near the al-Bureij refugee camp in central Gaza.
At least 12 Palestinians, including five children aged 12-15, were killed in that attack, said Dr Moaiya Hassanain of the Palestinian health ministry.
Fadl Shanaa, a Reuters cameraman, was killed with two Palestinian civilians when a missile hit his vehicle. He had been travelling to the al-Bureij camp to cover the aftermath of the air raid there.
Car 'marked'
Jacky Rowland, Al Jazeera's correspondent in Jerusalem, said the car in which Shanaa was travelling was clearly marked with "press" symbols.
She said there were even "press" markings on the roof of the car and it was inconceivable that Israeli forces would have been unfamiliar with the car since they look over the territory with drones, helicopters and jets routinely.
An Israeli military spokesman expressed regret but said journalists entered a "combat zone" at their own risk.
"We regret the death of a photographer, but it must be pointed out that there's a war going on against armed terrorists who are extremists and dangerous.
"Members of the media or civilians put themselves in danger by entering a combat zone."
Cross-border raids
Five Palestinians, all of them from the armed wing of the Palestinian Hamas movement, were killed in clashes with Israeli troops earlier in the day.
The Israeli army said it lost three soldiers and that three more were wounded in an exchange of fire near the security fence between Israel and the Palestinian territory.
Hamas said that it killed the soldiers in a "sophisticated ambush" in Gaza City.
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Hamas said that it carried out a "sophisticated
ambush" on Israeli forces in Gaza City [AFP] |
Israel said t
he soldiers entered Gaza in pursuit of two Hamas fighters who planted a bomb near the border and were ambushed by another Hamas force.
Other troops went in to the area and came under mortar fire from fighters.
The army said it responded with an air strike and identified hitting fighters in the al-Bureij area.
An Israeli army spokeswoman said troops exchanged fire with Hamas fighters at several points, hitting some.
In one battle, Israeli troops were "targeted by Palestinians and there were several casualties", she said, adding that there had been several incidents and that Palestinians had used anti-tank missiles and mortars as well as assault rifles.
Hamas officials said that the Israeli soldiers were supported by helicopters during the fighting near the Nahal Oz border terminal.
War of words
Israeli government spokesman Mark Regev called the deadly Hamas ambush a "provocation", describing Israel's military operations as "defensive".
Mahmoud Abbas, the Palestinian president, condemned the "Israeli aggression in Gaza" and urged all sides to "co-operate with Egyptian efforts to reach a truce to halt the bloody cycle of violence".
But Sami Abu Zuhri, a Hamas spokesman, threatened revenge against Israel and said "there can be no discussion of a truce in the midst of these crimes".
Palestinian fighters attacked the border crossing last week, the only terminal for supplying fuel to the Gaza Strip and its 1.5 million people.
Two Israeli civilians, two Palestinian civilians and two fighters were killed in that attack.
Fuel shipments resume
Fuel deliveries, which were halted after the April 9 attack, resumed on Wednesday, Israeli and Palestinian officials said.
Israeli officials had said earlier on Wednesday that the terminal would not be reopened.
The move to resume fuel deliveries came a day after the UN called for Israel to re-open supplies to Gaza civilians.
Mahmoud Khuzandar, the deputy director of the Gaza fuel station owners' association, said Israel had pumped 90 tonnes of liquid gas for cooking and 180 thousand litres of fuel for the power station into Gaza.
However, an Israeli defence official said that they had only sent fuel for a power plant.