"Banks at that time were set up in containers which were at various locations so that people could bring their money and open accounts," Cabraal said.
"IDPs had come from various parts particularly through water and the cash they carried were so muddy and soiled we really had to do money laundering as well," he quipped.
Sri Lanka's military effectively crushed the separatist Tamil Tigers in May 2009 ending a three decade conflict hat had taken a toll on the island's north and east.
During the final stages of the battle thousands of civilians trapped in rebel controlled areas had to brave the fighting and cross hostile terrains including a lagoon to enter government controlled areas.
Cabral said since hostilities ended banking services have grown in the former war zone amid challenges allowing people to start up livelihoods.
The Central bank says lending was extremely challenging because people lacked securities to offset loans and title deeds to land.
"It is very difficult to disburse small loans and if you are going to give a loan of 100,000 or 200,000 rupees to a person who has no security and a person who has been in conflict earlier, how does the bank take a decision of that nature," Cabraal said.
"People said they like to cultivate but they didn’t have title to the land and that title deeds were destroyed,"
"New innovations had to be created, we got the banks to go in and give small loans so that people could start up with water pumps, tractors and boats," he said.
Governor Cabraal said most of the small loans were given on concessionary rates and refinanced by the central bank and the finance ministry.
Sri Lanka's Northern Province which had been badly hit by three decades of war had the highest rate of economic growth in 2011 as a post-war revival continued, the central bank issuing provincial growth data said
The north's gross domestic product grew 27.1 percent in 2011 from 21.8 percent in 2010 increasing its contribution to the overall GDP to 3.7 percent last year from a year earlier.
The Central bank says growth was mainly driven by improved performance in the agriculture sector supported by the expansion of banking service in the region.
Cabral says the bank branch network grew rapidly in the north and east with the number of branches increasing up to 193 from 117 and accounts growing up to 6 million from 2.5 million within three years of the conflict ending.
The loan to deposit ratio of banks in the north was as low as 19 percent in 2009 indicating only 19 cents of every rupee of deposits were loaned in the area. But by September 2011 it has climbed to 52 percent from 32.88 percent by end 2010, data showed.