Stock Market in a Free Fall

The Dow closing down nearly 400 points for the second time this week, China forced to halt trading. Tune into World News Tonight with David Muir weeknights at 6:30 | 5:30c on ABC for breaking news, world reports, Made In America segments and other extraordinary stories. Watch more stories from World News Tonight with David Muir here: http://abcnews.go.com/WN Follow anchor David Muir across digital platforms— Facebook: https://www.facebook.com/davidmuirabc?fref=ts Twitter: https://twitter.com/davidmuir Instagram: https://instagram.com/davidmuirabc Follow World News Tonight— Facebook: https://www.facebook.com/WorldNewsTonight Twitter: https://twitter.com/wntonight Instagram: https://instagram.com/abcworldnewstonight/"