JERUSALEM — Palestinian militants detonated a bomb next to an Israeli army patrol along the border with Gaza today, killing one soldier and wounding three in the first serious clash since a cease-fire went into effect more than a week ago.

Israeli soldiers briefly crossed the border in search of the attackers, and Defense Minister Ehud Barak called an urgent meeting of Israel's top defense officers, saying Israel "cannot accept" the attack.

"We will respond, but there is no point in elaborating," Barak said.

The explosion jolted the calm that has largely prevailed since Israel ended a devastating three-week offensive on Jan. 17. Since withdrawing its troops, Israel has threatened to retaliate hard for any violations of the truce.

The flare-up came as Gazans struggle to resume normal life after the fighting, and as international donors discuss how best to help the territory rebuild. Gaza's Hamas leader said today the group — which is boycotted as a terrorist organization by the U.S. and European Union — would not try to claim any of the reconstruction funds, an announcement that appeared aimed at clearing the way for money to start flowing.

The announcement from Ismail Haniyeh, who remains in hiding because of fears he could be assassinated by Israel, appeared directed at donors who were concerned their funds could end up in Hamas' hands.

"Our aim now is to ease the suffering of our people and to remove the aftermath of the aggression in Gaza," the statement said. "Therefore we emphasize that we are not concerned to receive the money for rebuilding Gaza and we are not seeking that."

The Israeli military said the bomb targeted an Israeli patrol near the border community of Kissufim. There was no claim of responsibility.