Afghanistan's defiant vice president made one thing clear as the Taliban seized control of the capital following the collapse of his government -- he will not surrender. It appears Amrullah Saleh has retreated to the country's last remaining holdout: the Panjshir Valley northeast of Kabul. "I won't dis-appoint millions who listened to me. I will never be under one ceiling with Taliban. NEVER," he wrote in English on Twitter on Sunday, before going underground. A day later, pictures began to surface on social media of the former vice president with the son of his former mentor and famed anti-Taliban fighter Ahmed Shah Massoud in Panjshir -- a mountainous redoubt tucked into the Hindu Kush. Saleh and Massoud's son, who commands a militia force, appear to be putting together the first pieces of a guerilla movement to take on the victorious Taliban, as fighters regroup in Panjshir. - 'Resist with all our might' - Famed for its natural defences, the valley never fell to the Taliban during the civil war of the 1990s, nor was it ever conquered by the Soviets a decade earlier. "We will not allow the Taliban to enter Panjshir and will resist with all our might and power, and fight them,"...