Shafaq News/ Taliban insurgents have seized Afghanistan's second- and third-biggest cities as resistance from government forces crumbled, stoking fears that an assault on the capital Kabul could be just days away.
A government official confirmed that Kandahar, the economic hub of the south, was under Taliban control as international forces complete their withdrawal after 20 years of war.
Herat in the west also fell to the hardline Islamist group.
"The city looks like a frontline, a ghost town," provincial council member Ghulam Habib Hashimi said by telephone from Herat, a city of about 600,000 people near the border with Iran.
"Families have either left or are hiding in their homes."
A senior U.S. defence official said there was concern that the Taliban - ousted from power by U.S-led forces in 2001 after the 9/11 attacks on the United States - could make a move on Kabul within days.
But Washington was hoping the Afghan security forces would put up more resistance as the insurgents move closer to the capital.
The fighting has raised fears of a refugee crisis and a rollback of gains in human rights since the Taliban were ousted. Some 400,000 civilians have been forced from their homes since the beginning of the year, 250,000 of them since May, a U.N. official said.
"The situation has all the hallmarks of a humanitarian catastrophe," the U.N. World Food Programme's Thomson Phiri told a briefing, expressing concern about a "larger tide of hunger".
Of Afghanistan's major cities, the government still holds Mazar-i-Sharif in the north and Jalalabad, near the Pakistani border in the east, in addition to Kabul.
Families were camping out in a Kabul park with little or no shelter, having escaped violence elsewhere in the country.
The United Nations has said a Taliban offensive reaching Kabul would have a "catastrophic impact on civilians". But there is little hope for a negotiated end to the fighting, with the insurgents apparently set on a military victory.
The Taliban also took the towns of Lashkar Gah in the south and Qala-e-Naw in the northwest, security officials said. Firuz Koh, capital of central Ghor province, was handed over without a fight, officials said.
The militants, fighting to defeat the government and impose their strict version of Islamic rule, have taken control of 14 of Afghanistan's 34 provincial capitals since Aug. 6.
After seizing Herat, the insurgents detained veteran commander Ismail Khan, an official said. They had promised not to harm him and other captured officials.
A Taliban spokesman confirmed that Khan, who had been leading fighters against the Taliban, was in their custody.
Khan, the most prominent militia commander and believed to be in his 70s, together with the provincial governor and security officials, were handed over to the Taliban under an agreement, Hashimi told Reuters. He had no details of the deal.
Khan's capture, confirmed by Taliban spokesman Zabiullah Mujahid, provided one of the most potent symbols of the crumbling of resistance in the city.
Photos and videos showing the eminent commander apparently in the hands of the insurgents were widely shared on social media although they could not immediately be verified.
Ismail Khan is widely known as the Lion of Herat. His involvement in Afghanistan's wars goes back to the anti-government uprising that helped trigger the 1979 Soviet intervention, and his return to the front lines a month ago was a clear sign of the growing threat to Herat.