The Sarjapura police arrested 13 illegal immigrants, including four Bangladeshi women, from Kommasandra village off Sarjapura Road on August 22.

A police officer said locals tipped off the police as they observed the immigrants speak a particular Bangla accent, typical of Bangladeshi nationals.

The arrested have been identified as Mohammed Shafiq-Ul-Islam (20), Mohammed Habib Khan (45), Mohammed Shahin Kaghi (26), Ismail Khan (25), Mohammed Rakib (20), Mohammed Rubedar Porugi (22), Babul Khan (45), Mohammed Arif Sikhdar (18) and Mohammed Saddam Hussain (22). The four women are Tanya (20), Khakili (42), Asma (25) and Mohul-Shumi (22).

The foreign nationals lived in sheds put up by a local resident, identified as Nagesh. While one group has been living in the area for nearly a year, another joined them six months ago, prompting the locals to notice them.

The Bangla dialect was a dead giveaway and one of the local residents informed the police during Bakrid.

On the same day, the police picked up Mohammed Shafiq-Ul-Islam and questioned him. Shafiq-Ul-Islam revealed that the group entered India through the forest areas along the porous Indo-Bangla borders. They had no visas or passports.

Based on the information gathered from Shafiq-Ul-Islam, the other 12 were taken into custody. Four of the men are being questioned in police custody, while nine others, including the women, have been remanded to judicial custody.

The Sarjapura police have booked them under Section 14A(b) of the Foreigners Act, 1946 (enters into or stays in any area in India without valid documents).

The police are also investigating if the group could be a part of espionage activities or if they are linked to terror outfits, a police official said.