BEIRUT — Lebanon’s Hezbollah group confirmed on Saturday that its leader and one of its founders, Hassan Nasrallah, was killed in an Israeli airstrike in Beirut the previous day. A statement Saturday said Nasrallah “has joined his fellow martyrs.” Hezbollah vowed to “continue the holy war against the enemy and in support of Palestine.” [time-brightcove not-tgx=”true”] Nasrallah, who led Hezbollah for more than three decades, is by far the most powerful target to be killed by Israel in weeks of intensified fighting with Hezbollah.