Afghanistan's army has launched a counteroffensive to retake a key district in the north from Taliban fighters.
Earlier on Sunday, the Taliban seized control of Chardara district in Kunduz province amid reports that the group was moving closer towards the provincial capital, Kunduz city.
At least 12 Afghan soldiers were killed and 17 others were wounded in the fight over Chardara.
Mohammad Yusouf Ayubi, head of Kunduz's provincial council, said Taliban fighters established control of Chardara after two days of attacks on local security forces.
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He said local residents had fled their homes seeking safety.
Al Jazeera's Jennifer Glasse, reporting from Afghanistan, said this was the first time that the Taliban had taken control of an entire district in years.
Sayed Sarwar Hussaini, spokesman for the provincial police chief, said reinforcements were being dispatched and an operation to retake the district was imminent.
Afghan army and police forces have sustained heavy losses on the field against the Taliban following the departure of international combat forces at the end of last year.
Without NATO's support, the Afghan soldiers are struggling.
"We don't have air support. We only have ground troops. We don't have proper weapons," Atta Ullah, an Afghan soldier, told Al Jazeera.
"We only have M16s and if you fire three bullets, then the gun jams. Whatever we have, we will fight the Taliban to the last drop of blood."
Zabihullah Mujahid, a Taliban spokesman, claimed responsibility for the Chardara attack in an emailed statement to Associated Press news agency, and claimed there were heavy casualties among Afghan security forces.
The Taliban also attacked a police checkpoint in Ghazni in central Afghanistan, killing six police officers.
The Taliban has been carrying out attacks in across the country since late April.
Afghan authorities have repeatedly tried to jump-start talks with the Taliban in the hope of ending the 13-year conflict, but the group has set tough conditions, including the withdrawal of all foreign troops stationed in Afghanistan.
The Taliban takeover of Chardara came just hours after a roadside bomb in the southern Afghan province of Helmand killed several people, including nine children under the age of five.
No one has claimed responsibility for the attack on Saturday, but the Taliban routinely plants bombs along roads.
Source: Al Jazeera and agencies