KABUL, Afghanistan — Afghan forces backed by a U.S. airstrike launched a "large-scale operation" to rout the Taliban from a key city after militants seized a provincial capital in a stunning setback for the Western-backed government.
President Ashraf Ghani said Tuesday — his one-year anniversary in power — that reinforcements were arriving in Kunduz and were working hard to protect the lives of civilians.
"Our main problem is that the enemy is using civilians as shields," he said in a televised address. "We have predicted that this year will be the most challenging year for our forces, unfortunately our prediction was true."
The Taliban took the strategic northern city of Kunduz on Monday in a surprise multi-pronged attack that kicked off before dawn. It was the first major urban area to fall to the Taliban since the U.S.-led invasion of Afghanistan in 2001 and marks an escalation of the insurgency.
The victory came just days after new Afghan Taliban leader Mullah Mansourraised the possibility of resurrecting peace talks with the government in Kabul. The first round of negotiations was held in Pakistan in early July but the talks collapsed after it became known that Mansour's predecessor Mullah Omar had been dead for two years.
The militants called the seizure of Kunduz an "immense conquest" in a statement urging its fighters to respect the locals and which attempted to reassure Kunduz residents the Taliban had "no intention" of looting, violating their property or carrying out extrajudicial killings.
"Carry out your ordinary livelihoods in absolute security," it said in the statement. "All traders, workers, staff of hospitals, municipality and governing bodies should continue their daily routines without any fear or intimidation."
Kunduz resident Shah Wali said fighters were riding through the streets on motorcycles and trucks.
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"We have not gotten out of home and spent the night without electricity and running water," Wali said. "Last night it was largely quiet in the city center, with sporadic gunshots ... but firing has intensified since 8 a.m. this morning and is getting closer to the city center."
Images coming out of Kunduz showed Taliban fighters adorning bikes with their flag, driving Red Cross vehicles, snapping selfies in front of United Nations cars and tearing down posters of politicians in the city square.
Ministry of the Interior spokesman Sediq Sediqqi confirmed that a "large-scale" operation was underway on Tuesday to reclaim Kunduz, with some areas inside the city already "cleared" of Taliban.
"The operation to retake the city has started," Sediqqi said.
U.S. forces launched an airstrike in Kunduz province to "eliminate a threat to coalition and Afghan forces operating in the vicinity," according to a spokesman for the coalition. The spokesman, Col. Brian Tribus, would not elaborate on the nature of the threat, how many coalition forces were in the area or if they were engaged in ground fighting.
Afghan police special-forces units from neighboring provinces — like nearby Baghlan — also were deploying to help retake the city.
It was unclear how many casualties — fighters or civilians — resulted from the battles. Afghanistan's ministry of public health said Tuesday that at least 16 dead bodies and 172 injured patients had been treated at hospitals in Kunduz province.
NATO officially ended its combat role in Afghanistan last year. A scaled-down coalition presence remains in the country, mostly for training and advising Afghan forces.
This article originally appeared on NBCNews.com.