The arrested people have no criminal background and were working as labourers. They have been identified as Arabali Shaikh Khulna, Moosa Mulla, Habibul Sardar and Ismail Khan, all from Khulna district of Bangladesh.

Every year, thousands of Bangladeshi nationals enter India illegally and settle down in places like Mumbai and Surat. To keep tabs on the illegal immigrants, the SOG had initiated a special drive.

The police carried out raids in the Bhindi bazaar area in Unn and Shubhashnagar in the Adajan area of Surat on Monday night and arrested the four.

The police said Arabali and Moosa were staying in Bhindi Bazaar since the last one year, while Habibul and Ismail were staying in the Shubhashnagar slums since the last six months. The four were involved in different labour works in the city, they said.

SOG Inspector R G Desai said these people come to Surat and other cities due to poverty back home in Bangladesh.

"After staying here for one year they return to Bangladesh with the saved money. The racket is operational along the international border near Kolkata and at Mohangaun in Bangladesh,” said Desai.