Thirty-one Bangladeshis who allegedly entered the country illegally were detained at Assam’s Guwahati railway station on Monday, PTI reported.

Railway Police Deputy Superintendent Iftekar Ali said the group was detained when they were about to board the Kanchanjunga Express to Agartala in Tripura on Monday morning. “They could not produce any valid document to prove their Indian citizenship,” Ali said, adding that they are from Bagerhat district in Khulna division of Bangladesh. Thirteen children were among those detained.

During preliminary questioning, those detained said they had entered the country around two years back and moved to Bengaluru where they did small jobs. “They reached Guwahati yesterday [Sunday] by the Bangalore Express and spent the night at the railway station itself,” Ali said, according to The Assam Tribune. “They were planning to go back to Bangladesh via Agartala.”

The Government Railway Police have filed a case under relevant sections of the Foreigners Act as well as the Passport Act. “Once the court proceedings are over, their repatriation process would be taken care of as per laid down norms,” Additional Director General of Police (Border) Bhaskar Jyoti Mahanta said.