The explosion, which struck early in the morning near the governor's building in Dawlat Abad district, also wounded 13 civilians, said Sayed Massoud Yaqoubi, the police spokesman in Faryab province.
Meanwhile, Kabul police chief spokesman, Hashmat Stanikzai, said four people were wounded when two rockets struck near Kabul's international airport overnight.
One of the projectiles hit a house near the airport, wounding four civilians inside it, including a woman, said Stanikzai. The other rocket struck an open area and caused no damage.
No one claimed responsibility for the attacks in Faryab and Kabul, but the Taliban have stepped up their offensive against Afghan security forces to undermine the Western-backed government as foreign combat troops prepare to withdraw by the end of the year.
