– The Taliban took control of a large police base in a remote part of northeastern Afghanistan after some 100 police and border guards surrendered and joined the insurgents following three days of fighting, security officials said Sunday.

The loss of the Tirgaran base in Badakhshan Province late Saturday marked the largest mass surrender since U.S. and NATO forces concluded their combat mission at the end of last year.

It highlighted the problems facing Afghan security forces, which have seen their casualties soar in the face of stepped-up insurgent attacks.

The police base had been cut off as heavy rains swamped roads into the area, said Gen. Baba Jan, the province's police chief. It wasn't clear why reinforcements hadn't been flown into the area, though the province's steep ­valleys make aircraft landings ­difficult.

"No reinforcements were sent to help the police at the base for the past three days when they were under the attack and finally they had no option: They had to join the Taliban," said Abdullah Naji Nazari, the head of Badakhshan's provincial council.

Jan said the local police commander also joined the Taliban and handed over the base's weapons and ammunition.

The Taliban issued a statement saying they captured the base along with 110 police officers, their local commander and the head of the local border police. It did not say whether the captives joined their ranks.

Associated Press