A suicide bomber targeted an Afghan army bus in Kabul on January 26.
A spokesman for the Afghan Defense Ministry said at least four people had died in the attack, including two civilians, one of whom was a woman.
The spokesman said 22 others were wounded.
It was the first major attack in the Afghan capital since January 17 when militants raided a popular Kabul restaurant, killing 21 people, most of them foreigners.
NATO combat forces are withdrawing from Afghanistan this year after more than a decade of fighting the Taliban, but negotiations have stalled over a deal to allow some U.S. and NATO troops to stay after 2014.
Based on AFP and Reuters reporting