The attack took place on Thursday night in the eastern part of the Afghan capital where dozens of security officers had congregated to protect a demonstration of shopkeepers that had been held earlier in the day.
First reports immediately after the blast put the death toll at six officers but police official Jan Agha said that by Friday morning, the number of those killed had significantly increased.
No one has so far claimed responsibility for the bombing but both Taliban insurgents and the Islamic State group's affiliate in Afghanistan have targeted the country's security forces in the past.