GAZA CITY, Gaza Strip - Hamas extremists in Gaza fired rockets and mortar shells at Israel for the first time in five months yesterday, retaliating for deadly Israeli raids in the Palestinian territories and leaving a largely successful Gaza truce in doubt.

The barrage, which came on Israel's 59th Independence Day, did not cause any damage or injury, but it marked the first time Hamas had acknowledged firing shells toward Israel since agreeing to the cease-fire. Hamas is tightly organized, and Israel says attacks from Gaza have the tacit approval of the group's political leaders.

Hamas gave conflicting predictions about the future of the truce - some officials said it was over, while others said it depended on Israeli actions.

The cease-fire, announced in November by Palestinian leader Mahmoud Abbas and Israeli Prime Minister Ehud Olmert, put an end to Palestinian rocket fire and Israeli attacks, including air strikes against Gaza extremists.

Israel stopped most of its military activity but kept vital Gaza crossings shut, citing security threats. And while Hamas rocket squads stayed on the sidelines, others, including Islamic Jihad, kept up the fire of homemade rockets almost daily at Israeli towns and villages near Gaza.

Israeli raids in the northern West Bank during the weekend and an Israeli missile strike in Gaza killed nine Palestinians, including two civilians. Israeli officials defended the raids as part of operations that they said had drastically reduced the number of attacks against Israelis.

Hamas called for attacks against Israel in response to the weekend raids. Yesterday's rocket barrage was the first sign the new Hamas line might signal the end of the truce.

"The cease-fire has been over for a long time, and Israel is responsible for that," Hamas spokesman Abu Obeida said on Voice of Palestine radio.

"We are ready to kidnap more and more, and kill more and more of your soldiers," Obeida said, referring to a soldier seized in June by Hamas-linked extremists.

Israel Radio, citing military officials, said yesterday's rocket attack apparently was meant to create a diversion to capture an Israeli soldier near the Gaza border.

Hamas said it launched 41 rockets and 54 mortar shells; the Israeli military said it could confirm only six rockets and eight mortars. Two rockets fell harmlessly in Israel, the army said.

Israeli helicopters fired missiles at mortar launch sites in Gaza, the military said.

Palestinian Prime Minister Ismail Haniyeh of Hamas defended the attack. "We made great efforts at keeping the truce," he said, "and there was a positive Palestinian position, but unfortunately this position was met by expanding [Israeli] aggression."