Maj. Gen. Mohammad Bagheri, the chief of staff of Iran’s armed forces, was among the dead, according to Iranian state media. Officials said a top nuclear negotiator was also killed.

The Israeli strikes killed at least three of Iran’s top military commanders, as well as nuclear scientists and other leadership figures.

The two powers have been exchanging barrages since Israel attacked Iran and killed many of the country’s top military leaders and scientists.

He was the younger brother of Yahya Sinwar, the former Hamas leader killed by Israel last year. Hamas did not immediately respond to the claim of his death.