At least 12 people have been killed and 31 wounded in a suicide bombing at a government ministry in the west of the Afghan capital Kabul.
Women and children were among the casualties, according to an official.
The attack happened as employees at the Department of Rural Rehabilitation and Development left early for Ramadan.
The Islamic State group (IS) has claimed responsibility for the blast, which came just two days after the Taliban agreed to its first-ever truce.
Its ceasefire with the Afghan government is due to run for three days during the Muslim festival of Eid al-Fitr later this month.
The government will continue its operations against other groups, such as IS, during the ceasefire.
Separately on Monday, at least 10 people were injured in an armed attack on a provincial education department building in the eastern city of Jalalabad, although the incident has not so far been claimed by any group.
Both IS and the Taliban have carried out deadly attacks in Kabul in recent months.
More than 30 people were killed in a blast at a Shia shrine in the capital in March, while almost 70 were killed in a bombing at a voter registration attack the following month. Both attacks were claimed by IS.
A BBC study from January found the Taliban are openly active in 70% of Afghanistan and now control or threaten more territory than before the foreign troops left.