Who is Congressman Paul Ryan?

Web extra: Moore, Okla., third-grade teacher Jennifer Doan's sternum and spine were fractured while she tried to save her students from the devastating tornado that killed dozens. She tells Vinita Nair she wishes she could have done more to protect the children.

Jamie Falwell had sought shelter from the tornado with her two-year-old son in her bathtub. Her husband, Matt, arrived home just in time to rush them to their neighbor's storm cellar. That decision saved their lives. Mark Strassmann reports.

Many of the clothes sold in American stores come from factories in Bangladesh, which has a history of workplace disasters. Following the factory collapse last month that killed over 1,000 people, Holly Williams went undercover to see what the conditions are really like.

London police say two men used a knife and a cleaver to hack a man to death. The man was then videotaped by an unharmed passerby and waited for police to arrive. Charlie D'Agata reports.

Ibragim Todashev, a friend of the accused Boston Marathon bomber Tamerlan Tsarnaev, was shot dead by an FBI agent during questioning in Orlando. Todashev was being questioned about a grisly triple murder believed to be committed by the two men. Bob Orr reports.

Lois Lerner, the IRS manager at the heart of the political targeting scandal, delivered an opening statement Wednesday before a congressional committee, but she refused to take any lawmakers' questions. Nancy Cordes reports.