Clashes broke out on Sunday between Iranian border guards and Taliban forces, officials said, with the Afghan side confirming one of their border officers was killed and another wounded.
Both sides accused the other of opening fire first, AFP reported.
"There was a clash between the border guards of the Islamic Republic of Iran and the Taliban forces," Meysam Barazandeh, governor of Iran's Hirmand county, was quoted as saying by Iran's Fars news agency.
He added that "the conflict was brief and has ended".
Fars reported that clashes took place on the Iranian side of the border, in the Shaghalak area of Hirmand country, in the southeastern province of Sistan-Balochistan.