Israel said Saturday that it killed Hezbollah leader Hassan Nasrallah, dealing its most significant blow to the Lebanese militant group after months of fighting. There was no immediate confirmation from Hezbollah.

Ali Karki, the commander of Hezbollah’s southern front, was among several senior figures also killed in the attack, the Israeli military claimed, along with Abbas Nilforushan, a prominent general in Iran ’s paramilitary guard, according to Iranian state media reports.