"I am convinced he was taken with the help of Libyans," Abu Khatallah's brother said
"The investigation also determined that he continued to plan further armed attacks against U.S. persons," Samantha Power wrote in a letter to the U.N.
Republicans suspect Hillary Clinton is behind the timely arrest of the attack's mastermind
A U.S. official, speaking on condition of anonymity, said Khatallah was being held aboard an American ship
Kerry has offered two other possible dates—June 12 or June 20—for his testimony, and has asked the committee to withdraw its subpoena
The network finally acts on its star correspondent's discredited Benghazi report.