Officials from Pune's ATS unit on Monday night detained the person, said the ATS official, adding that they would not disclose the youth's name as they weren't sure whether "he is one among the three missing youth."
ATS and the city police are probing the case of three missing youths of Malvani area in western suburb of Mumbai.
The three youths were identified as Ayaz Sultan (23), Mohsin Sheikh (26) and Wajid Sheikh (25).
The parents of the three men had registered a missing complaint with the Malvani police.
"We suspect that the three joined the IS and our probe is on to ascertain this," Malvani police station's senior inspector Milind Khetle said on Monday.
An official of the Anti-Terrorism Squad also said they suspect that the three youths have been radicalised into joining the Islamic State, and added that the ATS is probing the matter.
While Sultan went missing on October 30, the other two have been missing since December 16, the ATS official said.
According to police, Sultan left home on October 30 after telling his parents that he had to go to Pune in connection with a job offer he got from a Kuwait-based firm.
Mohsin left home on December 16, saying he was going to attend a friend's wedding. Wajid also left home the same day saying he had to get the name on his Aadhar card corrected, the police officer said.
Police strongly suspect that the three men were in touch with each other as they resided in the same area and also because two of them left home on the same day.
Based on statements of family members of the three youths, it appears they were highly radicalised, police said.
Police is trying to ascertain whether the missing men were brain-washed into joining the IS by someone personally or through Internet.
Notably, in May last year, four youths from Kalyan township in neighbouring Thane district had gone to Syria to join the IS. One of them, Areeb Majeed, returned and is currently in NIA custody while the whereabouts of the other three were not yet known.
Besides, a Pune-based 16-year-old Muslim girl, who was reportedly radicalised by her IS contacts abroad and brain-washed to go to Syria, was questioned by ATS sleuths earlier this month and sent to a de-radicalisation programme.
3 Mumbai youths may have left to join IS says ATS
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