US Democratic representatives Brian Baird and Keith Ellison expressed shock at the plight of the war-shattered Gaza Strip during a rare visit to the Palestinian enclave on Thursday. "The amount of physical destruction and the depth of human suffering here is staggering" Baird said in a statement issued jointly with Ellison during their visit which coincided with a similar trip by US Senator John Kerry.

The visits were the first by US lawmakers since Hamas, an Islamist movement Washington labels a terrorist outfit, took power in Gaza by force after having won legislative elections in 2006.

Ellison, a representative from Minnesota, harshly criticized restrictions on the delivery of desperately needed goods into the coastal strip that has been under a crippling Israeli blockade imposed after the Hamas electoral victory. "People, innocent children, women and noncombatants, are going without water, food and sanitation, while the things they so desperately need are sitting in trucks at the border, being denied permission to go in," he said.

"The stories about the children affected me the most," said Ellison. "No parent, or anyone who cares for kids, can remain unmoved by what Brian and I saw here."

Baird, from Washington state, said the situation he saw was "shocking and troubling beyond words."

"The personal stories of children being killed in their homes or schools, of entire families wiped out, and relief workers prevented from evacuating the wounded are heart wrenching," he said.

Ellison, the first Muslim elected to the US Congress, hailed US President Barack Obama for acting "quickly to send much needed humanitarian funding to Gaza for this effort."

"However, the arbitrary and unreasonable Israeli limitations on food, and repair and reconstruction materials are unacceptable and indefensible," Ellison added.

Ellison and Bair both stressed that their visit did not have the official sanction of the Obama administration.

They said they held talks with civilians and relief workers, while Palestinian officials stressed they did not meet with any representatives of Hamas.

During their visit, the pair visited Izzbet Abed Rabbo, a community in northern Gaza devastated during the deadly 22-day Israeli offensive that ended on January 18.

An estimated 14,000 to 20,000 homes and other buildings were damaged or destroyed during the military offensive in which more than 1,300 Palestinians, two-thirds of whom were civilians and including over 400 children, were killed.

"The first and most urgent priority must be to help the people in Gaza. At the same time, the rocket attacks against Israeli cities must stop immediately," Baird and Ellison said in their joint statement.

"Just as the people of Gaza should not be subject to what they have experienced, the Israeli civilians should not have to live in fear of constant and indiscriminate rocketing," they said.

On Friday, the two planned to tour the Israeli towns of Sderot and Ashkelon, which are regularly targeted by the rocket attacks from Gaza.

US Senator John Kerry on Thursday also made a visit to the Gaza Strip, but stressed this did not reflect a change of policy toward the territory's democratically elected leaders.

The visit "does not indicate any shift whatsoever with respect to Hamas," said Kerry, who heads the Senate's powerful foreign relations committee.

Kerry's first stop in the impoverished Palestinian enclave was the American school left in ruins by the deadly 22-day Israeli offensive that ended on January 18.

Talking to a Palestinian lawyer amid the dust and rubble, Kerry defended Israel for responding to the rocket attacks by Hamas and other Palestinian groups. "Your political leadership needs to understand that any nation that has rockets coming into it over many years, threatening its citizens, is going to respond," Kerry told Shar Habeel al-Zaim.

The US senator was presumably referring to Palestinian rockets and not Israeli rockets and missiles, which have also been shot into Gaza by the thousands over many years.

Under the terms of an Egyptian-brokered ceasefire that went into effect last June, Hamas was to reign in rocket attacks if Israel lifted its siege of the territory. However, while the Islamists managed to virtually halt the attacks, Israel did not honor its pledge.

However, the deal largely held until November 4, when Israel shattered the agreement by invading Gaza and killing seven Palestinians. The incursion prompted Gaza based fighters to resume rocket attacks, the stated reason for Israel's 22-day onslaught of the enclave.

"There is nothing in a visit that changes anything," said Kerry, who is also scheduled to visit Syria as part of his tour of the region.

"What has to change is behavior. What has to change obviously is Hamas's consistent resort to instruments of terror," he said in the Israeli city of Sderot before entering the Palestinian enclave aboard a UN vehicle.

"We feel very deeply that no one should have to live under this threat," he said after he and Israeli Foreign Minister Tzipi Livni inspected rockets fired by Gaza militants that are exhibited in Sderot police station.

Early on Thursday, Israeli helicopter-backed troops were reportedly involved in a firefight when they briefly entered Gaza. Two rockets and two mortar rounds were then fired in retaliation from the enclave and Israel responded with an air raid on smuggling tunnels on Gaza's border with Egypt. There were no reports of casualties.

Meanwhile, Egypt expressed its "indignation" on Thursday over Israel's decision to link a Cairo-brokered truce in Gaza with Hamas to the release of a seized soldier.

Cairo "feels indignation" after Wednesday's vote by Israel's security cabinet to make a truce conditional on the release of Gilad Shalit, a senior official told AFP.

The young conscript was captured by Gaza militants in a deadly cross-border raid in June 2006 that followed on the heels of dozens of arrests of elected Hamas representatives.

"Israel has demolished its credibility" and this attitude will "complicate the situation," said the official, who did not wish to be identified.

"It was clear from the beginning that the issue of the soldier was not linked to the truce agreement," he added.

"Egypt will not change its position. The Shalit case cannot be linked to the truce," he said echoing similar remarks made earlier this week by Egyptian President Hosni Mubarak.

Hamas insists that Shalit's release be negotiated separately as part of a prisoner exchange involving hundreds of Palestinians currently held in Israeli jails.