The clashes and the dire warnings underscored the tenuous hold authorities have on this strategic city whose fall to the Taliban was an embarrassing blow to President Ashraf Ghani.
The Afghan government has been criticized for ignoring warnings earlier of Taliban threats to the city.
Moreover, a bombing early on Saturday of a hospital in Kunduz belonging to Doctors Without Borders in which at least 22 people were killed has raised wider questions as to the circumstances that led to the prominent medical charity being hit in an apparent US airstrike.
Overnight, several militants managed to re-enter the city center and attack Kunduz police headquarters and other government buildings, said Sarwar Hussaini, the spokesman for the provincial police chief.
By this morning, some gunmen had pushed their way close to the main city square. "Fighting is also going on with the Taliban near the Ghazanfar Bank, close to main square," Hussaini said.
Kunduz residents reported hit-and-run attacks by the Taliban, with the insurgents making incursions into the city center from far-flung rural areas, engaging troops, then retreating again.
With the Taliban blitz, shops closed and people shuttered in their homes, as the humanitarian situation steadily worsened in Kunduz. Deliveries of food and other basic essentials have not been able to get in since the Sept. 28 Taliban assault.
