The robbers then escaped from the scene, the deputy superintendent of police said.
Three bike-borne assailants today looted Rs 21.30 lakh, out of which 20.10 lakh in old currency, from a Grameen Bank in Bihar's Gaya district.
The robbers decamped with the cash after holding branch manager of the Madhya Bihar Grameen Bank at gun point.
Out of the looted amount, only Rs 1.20 lakh were in new currency notes while the rest of the amount, Rs 20.10 lakh, was in demonetised notes of Rs 500 and Rs 1000, Gaya deputy superintendent of police Alok Kumar Singh said.
The three entered the Pandey Parsama branch of Grameen Bank and looted the money from the branch manager.
Apart from branch manager, there were only two customers inside the branch at the time of incident, he said.
The robbers then escaped from the scene, the deputy superintendent of police said, adding that police are investigating the incident.
Senior superintendent of police Garima Mallick, additional superintendent of police Balram Kumar Choudhary along with Singh and other officials have reached the spot.
(This story has not been edited by NDTV staff and is auto-generated from a syndicated feed.)