Telbar Hussein was nabbed at Adambakkam here after a photocopy shop owner alerted police when Hussein tried to exchange a fake Rs 1000 note at his shop, police said.
Information provided by him led to the arrest of another person, Mohammedgoel Ali, they added.
Ali, who was employed as a security guard in a private firm, led police to a construction site where FICN of face value of Rs 2.74 lakh was buried.
Police launched a hunt for one Saddam Hussein, also a native of Assam, who is believed to be the kingpin of the group, they added.