JABALIYA, Gaza Strip (AFP) - Three Palestinians, including two children, were killed by Israeli fire in Gaza as the UN delivered aid to Palestinian families trapped in the Jabaliya refugee camp.
Palestinian doctors identified the two slain children as Sliman Abu Ful and Raed Abu Zeid, both 14, and said their bodies had been ripped apart by what appeared to be a tank shell.
But the Israeli army insisted that the two, targeted in the camp in northern Gaza, had been "preparing to fire an improvised rocket".
"The pair were hit by a missile fired by a helicopter gunship," a spokesperson said.
"A drone flying over the area filmed two figures who were putting a rocket launcher in a firing position at an angle of 45 degrees," a second spokesman said.
"The two figures moved away and there was a flash. A first attempt at firing apparently failed. The two figures then came back and we did not allow them to go ahead with a second attempt."
But witnesses at the scene told AFP the teenagers had been rummaging through the ruins of a local youth club destroyed by armoured bulldozers two days ago.
They said they were hit by a tank shell and that no fire or flash had been seen at the scene.
A 17-year-old girl, Samah Udeh, was also seriously wounded in Jabaliya when Israeli soldiers opened fire from tanks at the entrance of the camp, according to Palestinian hospital sources and witnesses.
The UN Relief and Works Agency for Palestine Refugees (UNRWA) announced a successful delivery of aid to half of the 600 families, approximately 3,300 people, trapped in the Jabaliya camp.
They have been unable to leave their homes since September 28, when Israel launched its "Days of Penitence" operation in northern Gaza in a bid to stop Palestinian rocket attacks on the Jewish state.
"Most have exhausted their food supplies and many have seen their water and electricity connections to their homes cut by bulldozing operations," UNRWA said.
In a separate incident, a Palestinian gunman was killed by Israeli troops in the southern Gaza Strip, according to an Israeli military source.
"Two armed men were apparently trying to infiltrate Israel. One of them was hit and killed by our forces. The other one escaped" the source told AFP.
"Two explosive devices were found next to the body, which were meant for our forces," the source said, adding that the incident had taken place in the area of Khan Yunis, near the security fence separating the Gaza Strip from Israel.
Palestinian medics said, for their part, that three Palestinians had been moderately wounded in the same incident. There was no immediate report of a fatal casualty.
The attack, which took place east of the town of Khan Yunis, was not claimed by any group.
Meanwhile, a young Palestinian wounded by Israeli gunfire earlier this week in Jabaliya died of his injuries, as did a young man wounded by tankfire on Tuesday in the northern Gaza town of Beit Hanun, hospital sources said.
The deaths brought to 93 the number of Palestinians killed since Israeli tanks first poured into northern Gaza Strip.
Five Israelis have also been killed in the territory during the campaign.
A total of 4,456 people have now been killed since the launch of the intifada, or uprising, four years ago, including 3,428 Palestinians and 954 Israelis, according to an AFP tally.
Despite Israel's Gaza operation, two rockets launched from the Gaza Strip struck the southern Israeli town of Sderot on Thursday, causing no casualties but damaging a house, Israeli military sources said.
Meanwhile, the Arab League expressed its frustration at the US veto Tuesday of an Arab-sponsored draft resolution at the United Nations Security Council against the Israeli army's operation.
"We're fed up," said Said Kamal, deputy secretary general for Palestinian affairs at the Cairo-based organisation.
"We can't keep count any more of the number of times the Americans have used their veto on behalf of Israel at the Security Council," he said.
The draft called for the "immediate cessation of all military operations in the area of Northern Gaza and the withdrawal of the Israeli occupying forces from that area."
For his part, former Palestinian security minister Mohammed Dahlan warned Israel to expect "revenge" attacks in the wake of the offensive in the Gaza Strip.
"I don't think Israel will achieve anything with this operation," Dahlan told AFP. "Israel has killed 93 people and destroyed hundreds of houses. That will not bring security but a violent retaliation and revenge operations.
"Every Palestinian who has lost a son, a brother or a house thinks only of revenge."
Dahlan called on Israeli Prime Minister Ariel Sharon to "recognise the failure of this operation and the incapability of winning this battle by fire and blood."
And in Washington, US officials asked Israel for further clarification of comments made by a top aide to Sharon, who said this week the premier wants to sabotage the so-called "roadmap" for peace.
The State Department said Washington was pleased that Sharon's office had restated the prime minister's commitment to the peace plan but added that Dov Weisglass' comments needed additional explanation.
Weisglass was quoted in a newspaper interview as saying Sharon's plan to withdraw from Gaza was a deliberate attempt to undermine the roadmap's promise of Palestinian statehood next year.