IS claims bus bombing in Afghan capital
Dozens of people have been killed and scores wounded in deadly attacks that have punctuated the last two weeks of the fasting month of Ramadan, which ends Sunday.
A woman was killed and three others were wounded in the bus attack, Kabul police said.
The bombing was the second in the capital in as many days after 10 people were killed on Friday when a bomb ripped through a mosque as worshippers were performing rituals.
No group claimed Friday's mosque bombing but IS took responsibility for the attack on the bus.
IS has claimed several bombings in recent weeks, particularly attacks targeting Sunni-majority Afghanistan's minority Shia and Sufi communities.
Taliban officials insist their forces have defeated IS, but analysts say the militant group remains a key security challenge.
Kabul police meanwhile vowed to "ensure security" during the Eid al-Fitr holiday that marks the end of Ramadan.