In a major development in the Middle East, Tom Soufi-Burridge reports on the assassination of the mastermind behind the Oct. 7 terror attack in Israel, Hamas leader Yahya Sinwar, killed officials say, by Israeli forces in Gaza; Trevor Ault has new details on the tragic death of former One Direction star Liam Payne and what a preliminary autopsy report shows; Mireya Villarreal has the latest on the delayed execution of Texas man Robert Roberson, who would have been the first in the U.S. to be executed in a case of "shaken baby syndrome." ; and more on tonight's broadcast of World News Tonight with David Muir.