Two Afghan security guards have been killed and three wounded by a suicide bomber in Kabul.
Two other people were wounded in the blast in the Wazir Akbar Khan neighbourhood, which contains foreign embassies and the NATO headquarters.
Police told the BBC that the attacker detonated his explosives near one of the entrances to a US military base.
Security in Kabul has been tightened in preparation for the holy day of Ashura on Saturday, when Shia Muslims commemorate the 7th Century death of Imam Hussein, the Prophet Muhammad's grandson.
This time last year, a suicide bomber killed at least 56 people at a Shia shrine in Kabul. More than 160 others were wounded.