Hussain Khan Sanjani, the leader of the provincial council in Kapisa province, says Monday's explosion killed an Afghan local police commander along with his son, two body guards and one civilian.
He says 17 other people were wounded in the blast, which occurred around 11 a.m. in a bazaar in Tagab district.
Separately, the U.S.-led military coalition says a NATO service member died on Monday of wounds he received during an insurgent attack in southern Afghanistan. No other details were disclosed about the death.
So far this year, 198 NATO service members have been killed in Afghanistan.