Suicide attack in Kabul leaves civilian casualties
"The explosion was a suicide attack with civilian casualties," said the ministry of interior's deputy spokeswoman Marwa Amini.
A witness near the scene in western Kabul confirmed the blast.
"It was a big explosion that rocked our house. We also heard gunfire afterwards. Ambulances rushed to the area quickly," resident Samiullah, who goes by one name, told AFP.
The blast upends months of relative calm in the capital with speculation rife that the Taliban have refrained from attacking major urban centres in an effort to keep talks with the US on track.
Read more: Afghanistan sees record rise in attacks during US-Taliban talks
The last major attack in the capital was in November when at least 12 people were killed when a minivan packed with explosives rammed into a vehicle carrying foreigners during Kabul's morning rush hour.
Four foreign nationals were among those wounded in the attack that targeted an SUV belonging to a private Canadian security company, GardaWorld - in a crowded neighbourhood near the interior ministry and north of Kabul airport.