Those arrested on Thursday are Kausar Hossain Khan, 29, and Kamal Hossain Sarder, 29.
Detective Branch (DB) Deputy Commissioner ‘Mahbub’ said the two were suspected for involvement with the attempt to murder of blogger Asif Mohiuddin.
Mahbub said Khan was arrested from Mirpur Section-10 and Sarder from Shyampur’s Dholaiparh around 5pm.
Police had earlier arrested Saad Al Nahin , nephew of junior Labour and Employment Minister Mujibul Haque Chunnu, and one Masud Rana for their suspected involvement in the murder.
Nahin was arrested earlier over the murder attempt on blogger Mohiuddin two years ago. He was freed on bail around a year back.
DB Inspector Nibaran Chandra Barman, who is investigating the case over the attack on Mohiuddin, said Nahin had confessed to his link to militant outfit Ansarullah Bangla Team.
Police claim the Islamic outfit was involved in the murder of Niloy.