In one incident, clashes erupted after militants attacked a security checkpoint in Zakhil, a neighborhood in Police District 3 of provincial capital Kunduz city in early hours of Sunday, Esmatullah Muradi, provincial government spokesman, told Xinhua.

"The police officers fought back the attackers and the gunfight claimed the lives of two police officers and four attackers," he said.

In a similar incident at the same time, one police officer and three Taliban militants were killed in Saychinar area of Chahar Dara district, on outskirts of the city, the official added.

Fighting rages across the war-torn country and clashes between security forces and Taliban have been continuing in more than 20 out of the country's 34 provinces since early April when the Taliban launched an annual rebel offensive.

Fighting between government forces and Taliban fighters often intensifies in spring and summer, the period locally branded as the fighting season of the year.