Update(1250ET): Official confirmation is trickling in, ahead of a planned evening Netanyahu speech - where he's expected to issue an official declaration of Hamas leader Yahya Sinwar's death during fighting in southern Gaza:

ISRAEL FOREIGN MINISTER KATZ: HAMAS CHIEF SINWAR WAS KILLED IN GAZA

Katz's message to foreign leaders likely means a DNA match was made:

In a message to dozens of foreign ministers around the world, Foreign Minister Israel Katz confirms that Hamas leader Yahya Sinwar was killed, becoming the first Israeli official to do so on the record.

"The mass murderer Yahya Sinwar, who is responsible for the massacre and atrocities of October 7, was killed today by IDF soldiers," says Katz, according to his office. "This is a great military and moral achievement for Israel and a victory for the entire free world against the evil axis of radical Islam led by Iran," he continues.