"Around 9:10am this morning a suicide auto bomb exploded in Police District Nine of Kabul", interior ministry spokesman Najib Danish said, adding the target of the attack was not clear.
An Afghan police officer said the attacker killed three civilians and wounded five more in the eastern part of the capital.
Earlier this week, top US commander in Afghanistan John Nicholson said security in Kabul would be "the main effort" for worldwide powers helping Afghan defense and security forces.
The attack comes as the Afghan government has extended an olive branch to the Taliban by inviting them for peace talks.
Health ministry spokesman Wahid Majrooh told AFP at least four people had been wounded.
Deputy Interior Ministry spokesman Nasrat Rahimi said the suicide bomber had been driving towards G4S but "detonated himself before reaching the target".More news: Here's Fortnite Mobile Gameplay In Action On iOS
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The Taliban claimed responsibility for the blast that hit the Despechari area in eastern Kabul in the morning on March 17.
In December, General John W Nicholson Jr of the US Army said his country would deploy more troops in an advisory role to Afghan forces in 2018, on top of the 14,000 American soldiers already stationed in the country.
The deceased people were all civilians, reports said. While the latest blast was not on the scale of others that have killed scores of people recently, the constant stream of attacks in Kabul has undermined confidence in the Western-backed government of President Ashraf Ghani.
"They have done the bare minimum to appear responsive to our requests", the official added, citing the need to prod the Taliban toward the negotiating table and round-up militants.
In October, insurgents controlled or influenced almost half of Afghanistan's districts ─ double the percentage in 2015, the U.S. government's office of the Special Inspector General for Afghanistan Reconstruction said in January.