JERUSALEM, Nov. 5 (Xinhua) -- Israeli Defense Minister Ehud Barak said Wednesday that Israel would continue the truce with Hamas but need to foil any attack against Israeli citizens.

    "The Israel Defense Forces (IDF) will continue to prepare for all possibilities, including the scenario in which we must do something to thwart an attack," Barak was quoted by the website of local daily Jerusalem Post as saying during a tour in the periphery neighborhoods of the Gaza Strip.

    Around 40 Qassam rockets and mortar shells were fired from Gaza following overnight military operation of the IDF, during which three Israeli soldiers were injured and six Palestinian gunmen were killed.

    Israeli security establishment immediately ordered the full closure of all goods crossings between Israel and Gaza.

    It was the worst outbreak of violence since an Egyptian-brokered ceasefire took effect in June.

    The military action was aimed at destroying a tunnel which Gaza militants had dug under the border to try to abduct Israeli soldiers, according to an IDF spokeswoman.

    Israeli Foreign Minister Tzipi Livni blamed Hamas for exploiting the truce to dig tunnels for smuggling weapons, staging attacks or kidnapping soldiers.

    "The (Tuesday night) operation was necessary in order to preserve Israel security," she told local media. "Israel cannot tolerate such blatant violations of the truce."

    However, Hamas spokesman Sami Abu Zuhri said the Israeli attack was a major violation of the truce and proved that the Jewish state was not interested in observing the lull any more, without disclosing what Hamas would do in response.