Afghan officials say a multi-pronged Taliban attack on a district headquarters in northern Balkh province has killed at least 11 policemen.

Munir Ahmad Farhad, spokesman for the provincial governor, says the attack started early on Tuesday morning and triggered a gun battle that is still underway around the Shortepa district headquarters.

Taliban spokesman Zabihullah Mujahid says the insurgents have overrun the district - a claim that Farhad denies. The spokesman says reinforcements are on their way to Shortepa.

Mohammad Afzel Hadid, head of the Balkh provincial council, says he fears the casualty toll could rise further unless reinforcement arrive promptly as the district is in a remote area.

Taliban attacks have continued unabated even as Afghanistan held presidential elections last week and US-Taliban talks over a peace deal collapsed last month.