Hamas Leader Ismail Haniyeh Killed in Airstrike, Iran Vows Revenge Against Israel

BEIRUT — Hamas leader Ismail Haniyeh was killed by a predawn airstrike in the Iranian capital Wednesday, Iran and the militant group said, blaming Israel for a shock assassination that risks escalating the conflict even as the U.S. and other nations were scrambling to prevent an all-out regional war.

Iran's supreme leader vowed revenge against Israel, saying "We consider his revenge as our duty" after Haniyeh was killed in a residence he used in Tehran. The strike came just after Haniyeh attended the inauguration of Iran's new president in Tehran and only hours after Israel targeted a top commander in Iran's ally Hezbollah in the Lebanese capital Beirut.

The dramatic assassination of Hamas's top political leader threatened to reverberate throughout the region's intertwined conflicts, pushing Iran and Israel into direct conflict if Iran retaliates. The strike could also prompt Hamas to pull out of negotiations for a cease-fire and hostage release deal in the 10-month-old war in Gaza.

Hezbollah, which denied any role in a weekend rocket attack that killed 12 young people in the Israeli-controlled Golan Heights, said it was still searching for the body of Fouad Shukur, a top commander allegedly behind the rocket strike, in the rubble of a building hit in a Beirut suburb.

U.S. Secretary of Defense Lloyd Austin expressed hope for a diplomatic solution on the Israeli-Lebanon border, saying "I don't think that war is inevitable... I think there's always room and opportunity for diplomacy." However, international diplomats trying to defuse tensions were alarmed, with one Western diplomat saying the double strikes in Beirut and Tehran have "almost killed" hopes for a Gaza cease-fire and could push the Middle East into a “devastating regional war.”

Hamas' military wing said Haniyeh's assassination "takes the battle to new dimensions and will have major repercussions on the entire region." Iranian President Masoud Pezeshkian vowed his country would "defend its territory" and make the attackers “regret their cowardly action.”

In the West Bank, Palestinian President Mahmoud Abbas condemned Haniyeh's killing, calling it a "cowardly act and dangerous development." Political factions in the occupied territory called for strikes in protest at the killing. In April, an Israeli airstrike in Gaza killed three of Haniyeh's sons and four of his grandchildren.