The Special Task Force of Kolkata Police on Sunday arrested three persons from the southern part of the city for their alleged links to Pakistan's Inter Services Intelligence.
The STF of Kolkata Police has seized mobile phone SIM card which, it believes, was used by the three arrested suspected ISI agents to pass on information to the ISI of Pakistan.
The ISI network of spies has been operating in India for over a decade.
A handler of Pakistan's Intelligence Operative and one Border Security Force serving officer have been arrested.