By Matt Blake and Helen Lawson PUBLISHED: 06:02 EST, 3 November 2012 | UPDATED: 06:10 EST, 3 November 2012 The United States considered moving its Benghazi consulate a mile away to a CIA base a month before the deadly attack by militants linked to al-Qaeda which killed Ambassador Chris Stevens and three. A classified cable also reveals the U.S. mission drafted a contingency plan to suspend its operation as security in the Libyan city deteriorated amid increasing violence. The secret cable, sent to Secretary of State Hillary Clinton's office, reflected officials' concerns that the Libyan militia protecting the consulate could have been infiltrated by extremists.
@highlight
Classified cable shows U.S. recommended the consulate move into CIA base
@highlight
Consulate staff believed that Libyan militia guarding their compound had been infiltrated and found member of the unit photographing the base
@highlight
Four Americans, including Ambassador Chris Stevens, were killed in a six-hour, commando-style attack on the US Mission on September 11
@highlight
CIA Director David Petraeus did not attend the ceremony when the coffins arrived back in US to conceal the CIA operation in eastern Libya
@highlight
Al-Qaeda in North Africa and Islamist militia Ansar al-Sharia were implicated
@highlight
Timeline of CIA involvement blows open the dramatic sequence of events, revealing that of 30 American officials there, 23 were with the CIA
@highlight
CIA team had been operating out of a building known as 'the annex', less than half a mile away from the consulate in central Benghazi
fought off wave after wave of mortar and rocket attacks with just their handguns as they sought to infiltrate the compound and shepherd its @placeholder staff to safety.