NDS following a statement said the militants who are believed to be members of the Islamic Movement of Uzbekistan (IMU) will be identified and tried for their criminal act.
The statment further added that the video has no links with the 31 Hazaras kidnapped by the militants from Zabul province.
The group released a video which purportedly shows the beheading of an Afghan soldier while the group pledges allegiance to the Islamic State of Iraq and Syria (ISIS) terrorist group.
IMU is actively operating in northern provinces of Afghanistan and was previously operating under the shadow of the Taliban group.
A militant identified as Sadullah Urgenji appears in the video and distances the group from the Taliban group insisting that the Taliban supreme leader Mullah Omar is no longer viewed as their leader.
Urgenji says Mullah Omar has not been seen for some 13 years and, “according to Shari’a,” can no longer be leader, insisting that his group was recognizing the authority of the Abu Bakr al-Baghdadi, leader of the Islamic State group.
According to Urgenji the Afghan soldier was beheaded since numerous female IMU members were captured by the Afghan security forces in Faryab province recently.
He said a group of 30 Afghan soldiers have been taken hostage by Islamic Movement of Uzbekistan militants in retaliation for the detention of the female IMU members.
Urgenji also warned that more Afghan soldiers will be beheaded unless the Afghan government does not consider their demand to swap prisoners.