Defence Minister Manohar Parrikar said on Sunday that his ministry is under "attack" by monkeys, adding that two army personnel were always on duty outside his office to ward off simians.Attending a book release function in Panaji, Parrikar said that soon after he took over as defence minister and visited his office, he thought that the two personnel on guard outside it were sentries posted for security.The minister said he later realised that their primary task was to ward off and shoo away monkeys from slipping into the office premises."Monkeys from actual Ram Sena and not the Karnataka-based Rama Sene," Parrikar said in jest, referring to the Hindu right-wing organisation Sri Rama Sene which he, as the former chief minister, banned from Goa.Monkeys are a menace in Delhi's South Block, which houses three of the most powerful addresses -- the Prime Minister's Office, the defence ministry and the external affairs ministry.