At least 31 people were killed and 50 injured as the result of the explosion in Kabul, BBC reported.
The incident occurred on Sunday morning at a voter registration centre in the Afghan capital Kabul.
According to the source, the Afghanistan police officers and doctors are working at the scene.
As reported earlier, a suicide bomber blew himself up outside a voter registration center in Kabul. None of the extremist groups has claimed responsibility for the attack.