“We have one killed and one wounded; the cause of the clash is not clear yet,” the police spokesman of the southern Afghan province of Nimroze, Bahram Haqmal, told Reuters.

Maysam Barazandeh, the governor of the Iranian border area of Hirmand, was quoted by the semi-official news agency Fars as saying the clashes had stopped and there were no casualties.

Iran’s Tasnim news agency said clashes broke out after Taliban forces tried to raise their flag “in an area which is not Afghan territory”.

Local sources told Reuters that people living near the border on the Afghan side fled their homes to take cover when the clashes intensified.

Since taking over Afghanistan a year ago, Taliban forces have frequently clashed with the security forces of Iran, which neighbours the country to the west, as well as Pakistan, which neighbours it to the east.