The head of Pakistan Federal Investigation Agency’s cyber crime branch on Tuesday said data from “almost all” banks in the country was stolen during a recent security breach. The FIA is the country’s counter-intelligence agency.

Cyber Crimes Wing Director Mohammad Shoaib told Geo News that his agency has made several arrests in the case, “including that of an international gang”. He added the accused would pose as Army officials to withdraw money from banks. However, Shoaib did not reveal when the security breach occurred.

The Cyber Crimes Wing has written to the affected banks and is in the process of summoning their representatives for questioning. Shoaib said the banks were responsible for protecting the data and it was their fault if the breach occurred because of weak security infrastructure. “The hackers have stolen large amounts of money from people’s accounts,” he told Dawn News TV. “The recent attack on banks has made it quite clear that there is a need for improvement in the security system of our banks.”

Last week, at least six Pakistani banks had suspended the use of their debit cards outside the country and blocked all international transactions.