Two employees of Afghanistan's human rights body were killed in a bomb attack in Kabul on Saturday, the agency said.
The Afghanistan Independent Human Rights Commission said the pair died when a homemade "sticky bomb" attached to their vehicle exploded in the morning.
Kabul police spokesman Ferdaws Faramurz confirmed the attack, which has not been claimed by any group.
The United Nations Assistance Mission in Afghanistan condemned the killings. "There can be no justification for attacks against human rights defenders," it said on Twitter, calling for an immediate probe.
It comes less than a week after two prosecutors and three other employees from the attorney general's office were shot dead by gunmen on the outskirts of Kabul, according to Al Jazeera reports.