WASHINGTON – An independent review board on Tuesday presented to Congress its report on the Sept. 11 attack in Libya that killed a U.S. ambassador and three other Americans, findings the Obama administration hopes will bolster its assertion that diplomats took all reasonable measures to anticipate and respond to the violence, and end months of finger-pointing and recriminations over whether the deaths could have been avoided.

Diplomats and intelligence officers alike have spoken about the rising risk in Benghazi and growing debate over how to improve security before the attack, set against Ambassadors Chris Stevens' decision to keep the Benghazi diplomatic post open and even visit there on Sept. 11.

Late that evening, militants overran the lightly defended U.S. Consulate, setting fire to it and ultimately killing Stevens and information specialist Sean Smith. Militants later fired mortars at the CIA safe house where survivors had taken refuge, killing Americans Glen Doherty and Tyrone Woods, both former Navy SEALs working for the CIA who had come to help rescue the diplomats.