"Ansar-Al-Islam", which declared it as the "Bangladesh branch" of Al-Qaeda in the Indian Subcontinent, has reportedly claimed responsibility for the killing of secular blogger Faisal Arefin Dipan, local media reported on Saturday.
It also claimed credit for another attack on Ahmedur Rashid Tutul, another publisher of the slain blogger Avijit Roy's book, and bloggers Ronovipon Basu and Tareque Rahim, according to the Somoy TV.
The authenticity of the group's claims was yet to be confirmed.
Roy, an American of Bangladeshi origin and critic of religious militancy, was hacked to death in February.