US, Afghan operation to oust IS from east 'almost complete'
The campaign in Deh Bala, near the Pakistan border, was launched in April and had completed most of its objectives by early June.
However, final mine clearance operations are still ongoing, Lt. Col. Josh Thiel, from the US first special forces group told Reuters.
"This was one of the main green zones that did two things. One, it provided money, finance, logistics to [IS] and we've taken that away from them," he said.
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"Additionally, [IS] was using this as a site to prepare and move high-profile attacks on Kabul and Jalalabad," he added.
The operation, led by Afghan commandos and supported by US air strikes special forces teams, set up a base near the village of Gargari, where the militants were trying to establish their regional capital for the Islamic State Khorasan Province (ISKP) branch.
Heavy fighting erupted for several days, ending in early June with 167 IS fighters killed and large quantities of equipment seized.
ISKP first cropped up in Nangarhar four years ago and have since gained a reputation for their extreme brutality including beheadings and bombings.
Washington's war in Afghanistan is still ongoing after 17 years of unrest, making it the longest conflict in US history. The past few years have seen a particular escalation of the offensive against the Taliban, which has led to an upshoot in violence and casualties.
In 2017, more than 20,000 people died due to the conflict, including some 10,000 security forces, 10,000 Taliban members, and an estimated 3,438 civilians.