The four, including two engineering students (all aged between 23 and 25), were tracked down to Kolkata last week from where they were allegedly preparing to flee to Iraq, a senior police officer told PTI today.
The youths were "attracted" by the ISIS propaganda on social networking sites and net-based mobile messenger, he claimed.
"However, it were the parents who got "suspicious" about their children and got in touch with the City Police, who in turn picked them up from Kolkata last week based on their parents' information," the police officer said.
Reacting to a query, the officer further said the four youngsters were not in touch with ISIS operatives or vice-versa and it was only through social networking platforms that they were drawn to ISIS.