Border Security Force (BSF) troopers detained four Bangladeshi nationals with $203,100 in India's Tripura, police said on Wednesday.
"The four Bangladeshis, aged between 22 and 48 years were detained while they were returning to their country through the Srimantapur checkpost late on Tuesday," a police official said.
The cash in foreign currency was recovered from their bags.
Police said that the detainees were residents of Comilla and were carrying valid passports.
The BSF has handed over all four to the police. Senior intelligence officials are interrogating them.
"The Bangladeshi men told the police that they were couriers of the US dollars. A man in Kolkata entrusted them to carry the foreign currency and hand it over to a Bangladeshi national," the official said.
The youths came to Tripura on Tuesday from Kolkata by plane.
Tripura shares 856 km borders with Bangladesh.