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    Texas woman: ‘Nightmare’ terror attack in Nice killed my husband, son

    02:49
  • Cellphone Video Captures Moment of Truck Attack Horror

    00:38
  • Spit and Garbage Left at Site of Truck Attacker’s Death

    00:34
  • Drone Shows Massive Scale of Nice Memorial

    00:33
  • Nice Attacker’s Father Speaks out on Son’s Troubled Past

    02:26
  • French Authorities Try to Identify Unknown Child Victim

    00:23
  • The Bastille Day Attack: Heartbreaking Images from Nice

    01:55
  • The Bastille Day Attack: A New Normal?

    03:24
  • The Bastille Day Attack: The Fateful Day in Nice

    09:02
  • Inside the Attack: How the Deadly Terror in Nice Unfolded

    03:11
  • American Doctor in Nice Recalls Chaotic Scene Moments After Truck Attack

    02:06
  • Risk of Truck Attack Has Long Been U.S. Security Concern

    02:04
  • Two Americans Among the Victims in Nice Attack

    02:39
  • Watch Eiffel Tower Light Up Blue, White, Red

    00:20
  • A history of the terror attacks in France

    01:06
  • Vehicles Being Used as Deadly Weapons

    00:49
  • Teacher of Boy Killed in Nice Attack: 'Brodie Was a Superstar

    00:45
  • Memorial Service Held at Nice Cathedral

    00:37
  • Map of Bastille Day truck route

    00:08
  • Obama After Nice Attack: We Must Not Do Terrorists' Work

    00:45

Expert Michael Leiter: ‘Cancer’ of terror is an enormous challenge

03:22

Commenting on the deadly truck attack in Nice, France, on Thursday, Michael Leiter, former director of the National Counterterrorism Center, tells TODAY that even though French police are very experienced with large events like the Bastille Day celebration during which at least 84 people were killed, better security and education are required to beat the “spreading cancer” of terror through social media. (Run time: 3:22)