A special team of Police Bureau of Investigation (PBI), on Wednesday arrested four including the prime accused Nazmul Islam of a case filed over an attempt to murder Liberation War Museum Trustee Dr Sarwar Ali.
The accused were detained in a drive from different parts of the country, PBI (North) said today.
The arrestees are former drivers of the trustee Sheikh Nazmul Islam, 30, and his aides - Sheikh Roni, 25, Md Monir Hossain, 20, and Md Foysal Kabir, 26.
The PBI team also recovered the materials from them used in robbery.
On January 5, the accused attacked Dr Sarwar and three of his family members at his Uttara residence in the capital.
Police later arrived at the scene and recovered seven machetes, a mobile phone set, an electric water heater, chemical spray and synthetic rope from the spot, left behind by the attackers.
Sarwar filed a case with Uttara West Police Station accusing the two attackers and four to five unidentified people.
After analysing residence security guard Hassan's mobile phone, law enforcers found that he had talked with Dr Sarwar's former driver Nazmul at least 30 times on that day.
Police arrested the security guard of the building in connection with the attack on January 6.