The Afghan Defence Ministry, however, said the airstrikes killed 30 Taliban fighters, but added an investigation was being made into claims that civilians were among those killed.

The Taliban launched the "massive attack" from several different points around the city overnight, said Sayed Sarwar Hussaini, spokesman for the provincial police chief, who reported "intense gun battles" around the city.

An Afghan official says at least 13 civilians have been killed in an airstrike that hit a residential house in a volatile district of eastern Nangarhar province.