Mohammad Yusouf Ayubi, head of the provincial council in Kunduz province, says at least 13 were killed in an attack on a checkpoint they were manning in Dashti Archi district, with another 15 security forces wounded.
The firefight began late Sunday and continued into Monday morning.
Meanwhile in Zawzjan province, Provincial Police Chief Gen. Faqir Mohammad Jawzjani says Fighting Monday morning with Taliban in Khamyab district left at least eight police killed, forcing the troops to withdraw from a district headquarters to avoid civilian causalities after intense fighting.
Three other police were wounded, he added, while seven Taliban were killed and eight were wounded.
Taliban spokesman Zabihullah Mujahid claimed both attacks.