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The Taliban said Monday it had "completely conquered" Panjshir province north of Kabul. The Islamist group sent thousands of fighters into Panjshir overnight to cement its control over the country a week after the last U.S. forces withdrew. "We tried our best to solve the problem through negotiations, and they rejected talks and then we had to send our forces to fight," Taliban spokesman Zabihullah Mujahid said in a Kabul news conference. 

Panjshir was an anti-Taliban stronghold, and the only province that didn't fall when the group swept Afghanistan in August. Its capture demonstrates the incredible strategic success of the Taliban's swift takeover: The Panjshir Valley sits between two large mountains, and it has just one entrance, making it particularly hard to seize. When the Taliban last ruled the nation in the late 1990s, Panjshir remained out of its grasp. The province also has some symbolic importance, as it was "the launching point for the U.S.-led invasion after the Sept. 11, 2001, terrorist attacks on New York and the Pentagon," The New York Times reported. 

"Yes, Panjshir has fallen," a senior official of the National Resistance Front of Afghanistan told The Washington Post. "Taliban took control of government offices. Taliban fighters entered into the governor's house."