Afghanistan has mobilised military reinforcements for a counteroffensive to take back Kunduz, a day after Taliban fighters overran the strategic northern city in their biggest victory since being toppled from power in 2001.
Tuesday's mobilisation came as the US carried out its first air strike on Kunduz, capital of Kunduz province.
US Army Colonel Brian Tribus, spokesman for the US and NATO missions in Afghanistan, said the raid was conducted "in order to eliminate a threat to the force", though there were no foreign troops left inside the city.
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Afghan security forces have retreated to the outlying airport, leaving the Taliban effectively in control of Kunduz after they stormed the city, capturing government buildings and freeing hundreds of prisoners.
Scores of unidentified bodies littered the streets after hours of heavy fighting on Monday, according to local residents, many of whom were making a hasty exit from Kunduz, some by road while others headed to the airport.
As of 11:30am on Tuesday, hospitals in Kunduz province had received 16 fatalities and 172 injured, Wahidullah Mayar, an Afghan health ministry spokesman, told Al Jazeera.
Al Jazeera's Qais Azimy, reporting from Baghlan, just south of Kunduz, said government troops attempted to re-enter the city but were foiled by intense gun battles.
At least one government soldier was killed and another one injured during the fighting.
Ayoub Salangi, the deputy interior minister, said security forces were ready to retake Kunduz and pledged to investigate how the Taliban managed to seize a major urban centre for the first time in 14 years.
However, government forces face intense resistance, with Taliban fighters blocking roads, carrying out ambushes and setting roadside explosives. Power lines have also been cut to foil a government counterattack, sources told Al Jazeera.
The fall of Kunduz, which has sent panicked residents fleeing, has dealt a major blow to the country's NATO-trained security forces and highlighted the insurgency's potential to expand beyond its rural strongholds.
The fighters have reportedly freed almost 600 prisoners, including former Taliban members, from jails in the city.
"This sends a message to the international community and Kabul, that the Taliban fighters are now capable of taking control of a provincial capital after 14 years," Al Jazeera's Azimy reported.
The development also coincides with the first anniversary of President Ashraf Ghani's national unity government coming to power, as it struggles to contain the insurgency.
It will, furthermore, boost the image of new Taliban leader Mullah Akhtar Mansoor within insurgent ranks as he seeks to drive attention away from internal rifts over his leadership.
"Yes, the enemy is in the city and they have taken over the prison and other buildings, but reinforcements are being deployed and the city will be taken back," Sediq Sediqqi, the interior ministry spokesman, told AFP news agency on Monday.
Zabiullah Mujahid, the Taliban spokesman, posted a triumphant picture on Twitter purportedly showing fighters raising the group's trademark white flag at a roundabout in the city centre.
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The Taliban's incursion into Kunduz barely nine months after the NATO combat mission concluded raises troubling questions over the capacity of Afghan forces as they battle the fighters largely on their own.
Kunduz province, which borders Tajikistan and is a major transport hub for the north of the country, could offer the Taliban a critical new base of operations beyond their traditional southern strongholds.
Before Monday's incursion, the Taliban made two attempts this year to capture Kunduz city, which has been encircled by the fighters for around a year now.
"As fighting rages in Kunduz, all sides must ensure that civilians and civilian objects are protected according to international humanitarian law," Amnesty International, the human rights organisation, said in a statement.
The Taliban has been largely absent from Afghan cities since being driven from power by the US and its allies, but has maintained rule over swaths of the countryside.
Kunduz, a Pashtun-majority province, was the last Taliban stronghold in northern Afghanistan in November 2001.
The fighters have stepped up attacks, starting with an offensive launched in late April against the internationally recognised government in Kabul.
The Taliban are believed to enjoy the backing of fighters from neighbouring Central Asian countries.
Taliban prisoners walk on a street after their comrades released them from the main jain in Kunduz city [AP]
Source: Al Jazeera and agencies