Interior Minister Bismullah Khan Mohammadi made the announcement Sunday, after attending the funeral of one of the murdered officials in Aybak, capital of the northern province of Samangan.
The main target of the attack is believed to be Ahmad Khan Samangani, a member of the Afghan Parliament who had previously commanded forces fighting the Soviets during the 1980s.
Samangani, whose daughter was the bride, was killed by a suicide bomber while greeting wedding guests.
Afghan National Police Gen. Sayed Ahmad Sameh, Mohammad Khan, the provincial head of intelligence, and an Afghan National Army division commander known only by a single name, Mohammadullah, were also killed in the attack.
The Taliban has not claimed responsibility for the attack, nor has it denied any involvement.