Corporation Bank — Corporation bank malkajgiri, anutex lane

I have signed a blank document stating that i am giving surety to my close friend but later i came to know they misused my signature and have given the loan to another person and i am dumbstruck how can a bank do such act. i request the authorities to take action as i am being tortured to pay the amount as i have given surety. How can i give surety to a person i hardly know ??. i have approached the bank manager and informed them but still not action was taken till date.

i am working in railways and have very meagre income not enough for me to run my daily requirements i have a small kid to look after and my salary is not enough for us and they are asking me to visit to court and pay the amount. kindly please look into the matter and do the need full please.