MIAMI - The family of Steven Sotloff, the second American journalist beheaded by Islamic State militants, said on Wednesday he was "a gentle soul", and challenged the group's leader to a debate on the peaceful teachings of the Muslim holy book, the Koran.
The group, which has captured territory in Syria and Iraq, released a video on Tuesday of Sotloff being beheaded. US officials confirmed its authenticity on Wednesday. President Barack Obama vowed to "degrade and destroy" the group.