Fierce gun battles raged for several hours late on Monday in the center of Sayyad district and outside the provincial capital, Sar-e-Pul, provincial council chief Mohammad Noor Rahmani said, Al Jazeera reported.
A high-ranking provincial official with an Afghan spy agency, a local police commander, and an army company commander were among the dead, provincial council member Mohammad Asif Sadiqi said.
Taliban spokesman Qari Yousof Ahmadi claimed responsibility for the attacks.
Sadiqi said at least 25 others were wounded in the attacks that began around 7 p.m. local time and continued for more than seven hours with Taliban militants overrunning the posts.
The attackers first stormed two security posts in the district center, Sadiqi added, before a reinforcement convoy that was sent to assist with repelling the Taliban was also ambushed by the militant group.
The Taliban have ramped up their attacks on Afghan security forces and government facilities in recent months, leaving troops thinly stretched throughout the country.
Last week, at least 12 Afghan security forces were killed in Taliban attacks in the northern Faryab and eastern Nangarhar provinces.