The Islamic State on Wednesday took over Tora Bora, which once served as Osama Bin Laden's mountain hideout in eastern Afghanistan, from Taliban fighters, according to Afghan officials and local elders.
Taliban fighters who had controlled the cave and tunnel complex fled after a week-long assault by ISIS, the New York Times reported.
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Hazrat Ali, a member of Parliament and prominent local warlord who helped American soldiers capture Tora Bora from al Qaeda in 2001, said ISIS was spurred to move against Tora Bora after the U.S. dropped the so-called "mother of all bombs" on one of its tunnel networks in April.
The U.S. military on April 13 dropped its largest non-nuclear bomb ever deployed, the Massive Ordnance Air Blast bomb, in eastern Afghanistan in the Nangarhar province, where it was targeting a network of ISIS tunnels and personnel in the Achin district.
"Some 1,000 ISIS militants were gathered close to Tora Bora, to capture the area," Ali told the Times. "I informed government forces to target them, and I told them they are trying to capture Tora Bora, but they did not pay attention."
Local Afghan police also confirmed that the Taliban's fortress fell to ISIS fighters.
"ISIS has captured Tora Bora and areas around it," an Afghan police official said. "The tribal elders are here in my office. They all escaped the area last night."
A local tribal elder from the Suleymankhel Valley, close to Tora Bora, confirmed the news as well.
"The Taliban escaped from the area last night and left us to ISIS with our women and children," Juma Gul said. "There was no resistance by the Taliban against ISIS, and local tribes had no way to fight them anymore, so we just escaped."
ISIS released an audio recording claiming it had captured Tora Bora, according to the Associated Press.
Local residents are angry at the Taliban and the Afghan government for allowing ISIS to take control of Tora Bora.
The Taliban's spokesman for that area, however, denied that ISIS had taken the mountainous area.
"Fighting is underway in the Tora Bora area between ISIS and our mujahedeen," Zabihullah Mujahid said. "It is the front line between our mujahedeen and ISIS. No one has advanced in the area."
Mujahid also accused the U.S. of carrying out airstrikes in support of ISIS.
Afghan President Ashraf Ghani on Wednesday ordered the 201st Corps of the Afghan National Army to move in against ISIS in the Tora Bora area.