The bearded man, wearing a 'khaki' coloured trousers, was immediately detained by the security personnel, including those of the IAF, after he apparently did not heed to the directive to open his bag.
Aiming their guns at him, the security personnel asked him to keep the bag away and lie on the ground.
The man was probed by the security personnel, including by Punjab policemen, about his antecedents and his movement.
This continued for about 15-20 minutes after which the man was taken away for proper questioning.
The man was let off after about 45 minutes as nothing objectionable was found from his bag, police sources said, adding his mental condition appeared to be unsound.
Personnel of the NSG, Army and Air Force, joined by Punjab policemen, earlier made a thorough check of his belongings in the bag which included some clothes, currency, visiting cards of a transport company and other papers.
His pockets were also searched by the security personnel and the jacket he was wearing was removed for a thorough check of his person.
The air base in Pathankot was attacked by six terrorists on Saturday last and the operation to flush them out continued till Tuesday.