Gunmen Claim to Kill West Bank Settler

Meanwhile, Gaza residents gathered at two crumpled bridges struck by Israeli missiles that left two key north-south highways impassable. Children scavenged broken guardrails and steel bars from the sites, piling them on the back of donkey carts as traffic backed up.

Israeli military officials said the targets, including the roads struck early Thursday morning, were chosen to limit the ability of Shalit's captors to move him around the densely populated strip or across its southern border into Egypt where a rescue operation would be more difficult to carry out.

Palestinian Authority President Mahmoud Abbas condemned the Israeli operation and called on the rest of the world to exert pressure on Israel to stop the campaign, which has yet to result in any deaths.

"The president considers the aggression that targeted civilian infrastructure as collective punishment and crimes against humanity," read a statement from Abbas's office.

Along the strip's southern edge in Rafah, Israeli troops and armor remained on the mothballed international airport after entering Gaza hours earlier. The modest incursion was the first by a significant number of Israeli ground forces since Israel completed the evacuation of its settlements and military bases in the strip last September.

Tanks appeared dug in behind dirt berms at the edge of the airport compound, as Palestinian gunmen made preparations in the event Israeli forces move into the city.

"We will sacrifice whatever we have," said Atif Zanoun, 28, who gathered with others on the final day of a mourning period here for one of the two gunmen killed in Sunday's raid on the Israeli post. "We have nothing to lose."

Also, the armed wing of Abbas's Fatah movement, the al-Aqsa Martyrs Brigades, asserted Wednesday that it had kidnapped a 62-year-old Israeli man. Israeli police said Noah Moskowitz of the central Israeli city of Rishon Lezion has been missing since Monday.

Olmert has ruled out negotiating for Shalit's release, rejecting a demand issued by his captors that the 421 Palestinian women and minors in Israeli jails be freed in return for information about the soldier's welfare. In its statement, however, the Palestinian Information Ministry noted that the Israeli government had done so in the past.

"The Israeli military escalation can't be the appropriate mechanism for releasing the Israeli prisoner," the ministry's statement said. "The Israeli leadership is going down the wrong path in trying to use the Israeli prisoner issue for political goals and to confuse the Palestinian internal situation."