One of the three youths from Mumbai who was suspected to have joined the Islamic State was detained in Pune by the Anti Terrorism Squad (ATS) on Tuesday.
The Mumbai Police began probing the case of the three youths -- 23-year-old Ayaz Sultan, 26-year-old Mohsin Sheikh, and 25-year-old Wajid Sheikh -- who went missing from the city's Malwani suburbs about two months ago, after their parents registered missing complaints.
Wajid Sheikh was detained in Pune and brought to Mumbai for questioning, The Indian Express reported.
"He is changing his statements continuously and therefore we have to subject him to a detailed interrogation. We are yet to reach a conclusion. We have to see if he has committed any offence under any anti-terror law," an official was quoted as saying.
Sheikh had reportedly told his wife that he 'wished to join jihad'.
The police suspected that the three men had joined Isis after their family members told them that they had been radicalised.
Last year, four youths from Kalyan near Mumbai had travelled to Iraq to join Isis, but one Areeb Majeed returned a few months later and was arrested.
So far, 23 Indians are said to have joined Isis in Iraq and Syria, even as several others have been stopped while attempting to join the terror group.
The Indian Home Ministry had said last month that Isis militants has been able to radicalise many youths in the country.
Nearly 150 Indians in the country have been put under surveillance after intelligence agencies warned that they were actively following the Islamic State's activities and propaganda online.