By Mirwais Harooni
KABUL (Reuters) - Taliban fighters overwhelmed an Afghan police checkpoint in a key province bordering the capital, killing six policemen on Tuesday as insurgents launch fierce attacks ahead of the withdrawal of foreign combat forces, an official said.
The bloody fighting season is testing the newly trained Afghan security forces' ability to battle the insurgency, which is determined to re-establish its strict Islamist state that was toppled 13 years ago in the U.S.-led military intervention.
The Taliban attacked the police post in Logar province early on Tuesday morning and the Afghan government forces were unable to repel them, according to a local official.
Six policemen died in the battle in Baraki Barak district, located about 100 km (62 miles) southwest of Kabul, the capital, district governor Abdul Rahim Amini said.
The battle came a day after a Taliban ambush in the mountainous northern province of Sar-e-Pul killed 22 policemen and soldiers.
Most international troops will leave Afghanistan at the end of this year, winding up the combat phase of the mission that began with ousting the Taliban over the shelter they gave the al Qaeda planners of the Sept. 11 attacks in the United States.
About 12,000 foreign military personnel, including 9,800 U.S. troops, are expected to stay on after 2014, to train and support Afghan forces continuing the fight against the Taliban.
(Reporting by Mirwais Harooni Writing by Kay Johnson; Editing by Clarence Fernandez)