At least seven people were killed and 25 wounded on Sunday when a suicide bomber on a motorcycle detonated explosives near a procession in Kabul commemorating the death of former anti-Soviet mujahideen commander Ahmad Shah Massoud, a government official said.
Police said the suicide attack came hours after another suspected suicide bomber was shot by police in Kabul before he could detonate his device.
Government spokesman Wahid Majroh said that seven bodies and 25 injured people were taken to the hospital from the attack site.
Earlier, gunfire could be heard across the city as demonstrators fired automatic weapons in aggressive displays of support for Massoud, an ethnic Tajik leader who was killed by suicide bombers in 2001.
At least 13 people were injured by gunmen firing their weapons into the air in defiance of a ban on celebratory gunfire, officials said.
With parliamentary elections approaching next month and rivalry between Afghanistan's ethnic groups on the increase, the annual commemoration day for Massoud has created a tense atmosphere in Kabul, where major roads were blocked by police.
The blast came four days after more than 20 people were killed by a suicide bomber at a wrestling club in Kabul as well as a secondary blast apparently aimed at first responders and journalists.