The four illegal immigrants -- Mohammad Nazrul, Mohammad Aslam, Salim Sheikh and Mohammad Hyat -- were arrested for entering India without valid documents in Bihar's Kishanganj town in 2006.
They had completed their jail term of three years in 2009 but had been waiting since then to return home, a police official said.
"All four had already served their jail term and have been finally released from the Kishanganj district jail," Superintendent of Police Manoj Kumar said, adding that the union home ministry had directed their release.
Kishanganj is some 350 km from Bihar capital Patna.
Patna: Four illegal Bangladeshi immigrants, languishing in a Bihar jail for more than three years after their term ended, have been released and handed over to the authorities of their country, police said on Saturday.
First Published: Saturday, March 09, 2013, 12:40