President Barack Obama has welcomed Iran's release of American Sarah Shourd and said he remained hopeful that Tehran would demonstrate ï¿½renewed compassionï¿½ by freeing her companions. Shourd, Shane Bauer and Josh Fattal were arrested last year after they crossed the border from Iraq without a visa. All three maintain they entered Iran mistakenly while they were hiking through Iraq but all three have been accused of espionage. Bauer and Fattal are still being held at Evin prison. Lisa Mullins talks with Iran expert Haleh Esfandiari who was imprisoned at Evin in 2007.