Who was the London Attacker?

Police reveal that the London attacker had a violent past and spent several spells in prison. The man originally identified as 52-year-old Khalid Masood killed four people, including a police officer, in Westminster on Wednesday.

Also in the programme: US Congress prepares to vote on reforming Obamacare and Newshour's Lyse Doucet is in Palmyra.

(Photo: A man takes photos of floral tributes on Westminster Bridge after attack. Credit: RATCLIFFE/AFP/Getty Images)