In Zabul on Friday "at least 25 members" of the Afghan army and the Afghan police were killed in an assault on a checkpoint that involved policemen on the inside working with the attackers, said local officials.

Atta Jan Haq Bayan, head of Zabul's Provincial Council, said "at least 20" security personnel were killed in the attack while the attackers were aided by "eight policemen who were pro-Taliban."

Another source-- a local official speaking on condition of anonymity, said it was six security force members on the inside who joined attackers.

The outpost was manned by Afghan army and police.

Sources in Zabul said the policemen who assisted in the attack also left with the Taliban.

This comes a day after acting Defense Minister Assadullah Khalid on Thursday afternoon announced that the security forces were switching from "defensive status" to "active defensive status" against the militants.

Later on Friday the Afghan Ministry of Defense in a statement pledged to respond to the Taliban's attack.

“At least 11 national army officers and 6 members of the police force were martyred as a result of a 'Taliban' attack that was conducted with the help of their infiltrators on a checkpoint today in the center of Zabul province,” said the statement.

“The Afghan National Security and Defense Forces will not let the attack go without a response and will avenge the bloods of the martyrs,” said the statement.