The head of the United Nations nuclear watchdog said on Monday that “very heavy damage” is expected at Iran’s underground facility at Fordo after a U.S. airstrike there this weekend with sophisticated bunker-buster bombs.

Initial military assessments of the buried nuclear site contrast with the statement on the strike there made by President Trump.

Iran's deep nuclear plant, after series of bunker-busting bombs dropped; experts worry that nuclear material was moved prior to the attack