World News Roundup

Historic prisoner swap with Russia means freedom for journalist Evan Gershkovich and former Marine Paul Whelan. Simone Biles dominates Olympics gymnastics once again. Thousands turn out in Teheran to mourn Hamas leader, believed killed by Israeli strike. CBS News Correspondent Jennifer Keiper with tonight's World News Roundup. Learn more about your ad choices. Visit megaphone.fm/adchoices