KABUL－The Taliban were in control of six Afghan provincial capitals on Tuesday after a blitz across the north forced tens of thousands of people to flee their homes for the relative safety of Kabul and other centers.

The insurgents now have their eyes on Mazar-i-Sharif, the biggest city in the north, in a region that has traditionally been anti-Taliban.

Government forces are also battling the hard-line Islamists in Kandahar and Helmand, the southern provinces from where the Taliban draw their strength.

With the United States due to complete a troop withdrawal at the end of the month and end its longest war, it has all but left the battlefield. However, its special envoy Zalmay Khalilzad has been sent to Qatar to try and convince the Taliban to accept a cease-fire.

The US State Department said Khalilzad "will press the Taliban to stop their military offensive", and "help formulate a joint international response to the rapidly deteriorating situation".

But Pentagon spokesman John Kirby said it was down to the Afghan government and its forces to turn the tide, saying there was "not much" the US could do to help.

On Monday, the Taliban said they were moving in on Mazar-i-Sharifa linchpin for the government's control of the region－after capturing Sheberghan to its west, and Kunduz and Taluqan to its east.

However, Fawad Aman, spokesman for the Afghan Defense Ministry, said Afghan forces have the upper hand there.

On the move

As fighting rages on, tens of thousands of people are on the move inside the country, with families fleeing newly captured Taliban cities with tales of mistreatment at the hands of the insurgents.

"We are so exhausted," said Farid, an evacuee from Kunduz who did not want to be further identified. He is now camped out with hundreds of families at a Kabul park after fleeing Sheberghan.

In Kunduz, residents said shops have begun to reopen in the center as insurgents focus their attention on government forces who had retreated to the airport. The city was captured by the Taliban over the weekend.

"People are opening their shops and businesses, but you can still see fear in their eyes," said shopkeeper Habibullah.

Another resident, living close to the airport, said there has been heavy fighting for days.

"The Taliban are hiding in people's houses in the area and government forces are bombing them," said Haseeb, who only gave his first name.

"From the window of my house, I can see women, children and men all leaving. Some of them are barefoot, … some are pulling crying children with them."

Agencies - Xinhua