Three Nigerian nationals, including a woman, have been arrested in Assam's Karimganj district for illegally crossing over from Bangladesh, police said on Monday.
During routine patrolling on Sunday night, the three foreigners were seen sitting inside a bus and asked to produce their passports and visa documents but they failed, police said.
They were taken to Churaibari police station and during interrogation, the foreigners claimed to have entered Tripura through the Indo-Bangladesh border, a senior officer said.
According to police, they were coming from Agartala and had a plan to go to Guwahati.
The foreigners were identified as Nnaemeka Chinondo Feix, Igneus Okafor and Igunbor Dopis, police said, adding that five mobile phones were seized from their possession.
The Nigerian nationals asserted that they had entered Bangladesh with visa documents and crossed the Indo-Bangladesh boundary with the help of a person of the neighbouring country, police said.
An investigation has been initiated, police added.