The Taliban captured another three provincial capitals in southern Afghanistan on Friday, including in Helmand, the scene of some of the heaviest fighting in the past two decades, as the insurgents press a lightning offensive that is gradually encircling the capital, Kabul.

The loss of Helmand’s provincial capital comes after years of toil and blood spilled by American, British, and allied NATO forces. Hundreds of foreign troops were killed there over the course of the nearly two-decade war.

The insurgents have taken more than a dozen provincial capitals in recent days and now control more than two-thirds of the country just weeks before the US plans to withdraw its last troops.

Attaullah Afghan, the head of the provincial council in Helmand, says that the Taliban captured the provincial capital of Lashkar Gah following heavy fighting and raised their white flag over governmental installations. He says that three national army bases outside of Lashkar Gah remain under the control of the government.

Atta Jan Haqbayan, the provincial council chief in Zabul province, said the local capital of Qalat fell to the Taliban and that officials are in a nearby army camp preparing to leave.