TUESDAY NIGHT: David Muir anchors a special edition of ABC World News Tonight with David Muir as Iran launches an attack on U.S. military facilities in Iraq after a U.S. drone killed Qassem Soleimani, with Ian Pannell reporting from Erbil on the latest details, Martha Raddatz in Tehran where Iranians were vowing revenge and Jonathan Karl at the White House where President Trump is being briefed.https://abcn.ws/2QOryIY | ABC World News Tonight with David Muir

TONIGHT: David Muir anchors a special 1-hour edition of ABC World News Tonight with David Muir live from Las Vegas in the wake of the nation's deadliest mass shooting. Follow ABC News for the latest developments. http://abcn.ws/2xVfcqU | ABC World News Tonight with David Muir

TONIGHT: David Muir anchors ABC News coverage from Beauregard, Alabama, where at least 23 people where killed by one of 40 reported tornadoes to strike the Southeast in the past 24 hours. https://abcn.ws/2NILURW | ABC World News Tonight with David Muir