The girl was gangraped allegedly by Bhowmick and his two friends, Ganga and Narayan Mondal, both in their mid forties, the sources said.
The girl's father lodged a missing diary with the police on February 27, following which Bhowmick threatened the girl's father, Nirmal Das, that his daughter would either be killed or sold off in Bangladesh and demanded that it be withdrawn, the sources said.
On assurances from the father, Bhowmik left the girl on the national highway on February 28, they said.
The girl's father lodged an FIR on February 29 with the police registering a case of gangrape against Bhowmik and his two friends.
The girl was sent for medical test which confirmed gangrape, the sources said.
Bhowmik and his two friends were absconding, they said.