Parwan province leader Abdul Basir Salangi says five people also were wounded yesterday in Bagram district. He says all of the victims were either laborers or security guards of the company working in a chromite mine.
No group has claimed responsibility for the bombing, but, in confirming the incident today, Salangi blamed the Afghan Taliban.
The Taliban have previously targeted people working for mines as well as other development and infrastructure projects in Afghanistan.
The militants have recently escalated their activities in the country as US-led foreign troops have begun drawing down their presence.