On national television Tuesday, President Ashraf Ghani told Afghans that security forces had begun retaking government buildings, adding that "reinforcements, including special forces and commandos, are either there or on their way there." The fall of Kunduz - the provincial capital and home to about 300,000 people on the northern border with Tajikistan - on Monday had sent panicked residents fleeing and dealt a major blow to Afghanistan's NATO-trained security forces.

"The enemy has sustained heavy casualties," Ghani claimed on Tuesday, urging Afghans to trust his troops and not give in to "fear and terror."

In one of the group's biggest gains since being ousted from power by US-led forces in 2001, the Taliban seized the provincial governor's office Monday. The assault came a day before Ghani's unity government marked its first anniversary; it also looks set to further complicate efforts to resume stalled peace negotiations.

'Very serious'

Early Tuesday, US military planes struck Taliban positions on the outskirts of Kunduz, a NATO spokesman said. By afternoon, Afghanistan's Defense Ministry announced that government forces had regained the city prison and the provincial police headquarters. Several other government facilities, including a 200-bed local hospital, remained under Taliban control.

The region surrounding Kunduz - the province controlled by the German military during the NATO-led occupation of Afghanistan from late 2001 to 2013 - has become the most dangerous in the country's north in recent years. Precise casualties from fighting Monday and Tuesday remain unknown.

Taliban spokesman Zabihullah Mujahid said, however, that the combat had left three of the group's fighters dead and 11 wounded, while at least 18 Afghan police had died. The Taliban often overstates casualties inflicted on government security personnel.

"We are sending more fighters from other areas to support local mujahedeen in their job," Mujahid said. "The situation is very serious, and intense fighting is going on between our mujahedeen and Afghan forces."

The Taliban's efforts have escalated since NATO withdrew almost all of its combat troops and shifted its focus to training Afghanistan's fledgling armed forces at the beginning of the year. A residual force of about 13,000 NATO troops remains for training and counterterrorism operations.

mkg/msh (Reuters, AFP, dpa, AP)