State Bank of India (SBI) has advised its customers not to use automated teller machines (ATMs) of other banks for the time being for safe transactions following reports of the biggest-ever cyber security breach in the country\u2019s banking system. The bank is aiming at replacing around six lakh debit cards, which have been blocked by it as a proactive measure, within 10 days, a senior SBI official has said.\u201cWe have set an internal target of seven to ten days for issuing new debit cards to customers whose cards have been blocked,\u201d said chief general manager (Kolkata Circle) Partha Pratim Sengupta. Speaking to the media at a press meet on Thursday evening, Sengupta said, \u201cWe advise our customers to use SBI ATMs only at the moment for safe transactions.\u201d The public sector lender on Wednesday said card network companies NPCI, Mastercard and Visa had informed various lenders about a potential risk to some cards owing to a data breach. \u201cAccordingly, SBI has taken precautionary measures and have blocked cards of certain customers identified by the networks. This has been a proactive measure to protect our customers from any potential fraud, once we came to know of some data breach outside our bank,\u201d SBI said in a statement, adding that it is in the process of issuing new cards at no cost. The malware-related security breach was reportedly detected in the non-SBI ATM network, following which the country's largest lender blocked around six lakh debit cards. According to NPCI,Rs 1.3 crore has been lost by Indian customers in this massive cyber security breach, putting as many as 3.25 million debit cards issued by various banks at risk.Data across cards are believed to have been stolen from ATMs of an Indian private sector bank that is serviced by Hitachi Payment Services. Meanwhile, SBI said it is eyeing close to 45% year-on-year growth in retail lending in the Kolkata Circle during this festive season (October to December). \u201cDuring this year festive season, our retail loan target is Rs 1,000 crore. Last year, the loan amount stood at around Rs 700 crore,\u201d Sengupta said. The bank is offering lower interest rates and zero processing fees on some of its retail products \u2013 home loans, car loans, personal loans and education loans under its special financing scheme, Hope Loans, during the festive season. \u201c.for every loan sanctioned during this period, the bank will contribute a sum to selected NGOs working in the field of education, health, environment and shelter which will help a disadvantaged person's dreams come true,\u201d a release said. The bank, however, has not yet decided on the percentage of the loan amount to be donated to the NGOs, Sengupta said.