LUCKNOW, Sept. 9 -- : The arrest of a Punjab National Bank (PNB) official by the National Investigation Agency (NIA) has intensified the probe into one of the biggest counterfeit-currency discoveries in Uttar Pradesh, with investigators now examining whether fake notes worth Rs.17.29 crore found inside a bank currency chest were part of a larger network operating through the formal banking system, informed senior NIA officials on Tuesday.

The NIA arrested Amit Kumar, manager of the Jagadhri currency chest on Monday and a key named accused in the case. He was among three PNB officials who came under the scanner after counterfeit Indian currency was detected at the bank's currency chest in Saharanpur's Sofia Market area.

The arrest is sig...