0:32

Anonymous tip system started after Sandy Hook shooting has fielded over 400,000 reports

The program, born in the grief of one of the nation’s worst mass shootings, teaches students how to identify warning signs among their peers and urges them to report any red flags to an anonymous tip system or a trusted adult to head off any violence.

2:53

Closed circuit TV captures armed man sprinting through security during White House Correspondents' Dinner

The video of the suspected shooter, identified as 31-year-old Cole Tomas Allen, of Torrance, California, is now generating questions about Trump's security and how a gunman could get so close to the president.