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After the fall of Kabul on August 15, Panjshir remained the holdout where resistance forces led by Ahmad Massoud, the son of former Afghan guerrilla commander Ahmad Shah Massoud, fought the Taliban.
The Panjshir fighting has been the most prominent example of resistance to the Taliban. On Sunday, Massoud said he was ready to cease fighting and start negotiations if the Taliban abandoned the province.
Panjshir, a rugged mountainous valley north of Kabul still littered with the wreckage of destroyed Soviet tanks, has proved very difficult to overcome in the past.
Taliban officials have said previously their forces had secured full control of Panjshir but fighting has been continuing for days. Pictures on social media showed Taliban members standing in front of the gate of the Panjshir provincial governor's compound on Monday.
Under Ahmad Massoud's late father, Ahmad Shah Massoud, Panjshir resisted both the invading Soviet army and the previous Taliban government. On Sunday, Massoud said hundreds of Taliban fighters had surrendered to the resistance forces.