LONDON: British army commanders were partly to blame for the inadequate defences and complacency that allowed the Taliban to attack a base in Afghanistan, killing two US marines, a parliamentary committee said on Wednesday.

The September 2012 attack on Camp Bastion in Helmand province saw 15 heavily-armed Taliban fighters dressed in US army uniforms cut the perimeter wire before destroying six US harrier jets and damaging many other aircraft and vehicles.

Two US marines were killed during the attack and 16 US and British staff as well as a civilian contractor were injured.

The committee said the perimeter security measures in place at the time of the attack were inadequate, with less than half of the camp's 24 guard-towers manned that night.

“Insufficient attention was given to the fundamental requirement of defending Camp Bastion from external assault. We believe that this was complacent,” the Defence Committee, which scrutinises government defence policy and expenditure, said in a report. “Given that the attack took place in the British sector of the camp, British commanders must bear a degree of responsibility for these systemic failures and associated reputational damage.”

Two US generals were forced to retire following a US review of the attack last year.

The committee said it was concerned that there had been a number of breaches of the perimeter fence in the two years before the attack, and that a tolerance of poppy cultivation immediately outside the fence had increased the risk of surveillance and intelligence gathering by Afghan nationals.

While it was satisfied that the camp's vulnerabilities had now been addressed, the committee asked the Ministry of Defence (MoD) to explain how it intended to use lessons identified from the attack for future operations.

Britain is preparing to withdraw the last of its troops from Afghanistan by the end of 2014.

Defence Secretary Philip Hammond said British commanders had identified and acted upon all lessons following the attack.

“The MoD is not complacent and always seeks to capture and learn lessons from current operations. Commanders in the field have to prioritise resources against potential threats in theatre and at the time a threat to Camp Bastion was considered to be lower than to other Isaf assets in Helmand,” he said.

Hammond rejected the committee's comment that the MoD had been “obstructive and unhelpful” to its inquiry, He said it had been given a considerable amount of classified information to help answer questions on the events surrounding the attack.