KANDAHAR, Afghanistan — At least six members of a militia belonging to the Afghan intelligence agency were killed in a suicide car bombing at their base in the southern province of Helmand, Afghan officials said Tuesday.

The attack late Monday was in Gereshk District, just outside the provincial capital, Lashkar Gah, which has been largely besieged by Taliban forces for more than a year.

Bashir Ahmad Shakir, the head of the security committee on the Helmand provincial council, said the bomber Monday had rammed his car into the base compound, on the main road leading to Lashkar Gah.

Hayatullah Hayat, the governor of the province, said six members of the service were killed and seven wounded in the attack, the Associated Press reported.

Officials said the death toll could rise because the explosion had collapsed structures on the base.

The dire situation in Helmand has drawn a renewed focus from the US-led NATO mission in Afghanistan. About 300 US Marines are expected to return to the province this spring.

Their deployment has great significance for the corps, which suffered many casualties during its long fight in the province, ending with the withdrawal of most NATO combat troops in 2014.

They will be replacing an advisory mission of US forces already in Helmand to help the Afghans hold the line.

On Sunday, three US Army soldiers were wounded about 45 miles away, in Washir District, when an Afghan commando guarding a tower opened fire.

New York Times