Iranian media say gunmen have killed eight border guards in the country's volatile southeast, near the border with Pakistan.
The semi-official Fars news agency reported that the attack took place on April 6 in the restive Sistan-Baluchistan Province.
The report said four of the soldiers killed were conscripts.
Ali Asghar Mirshekari, deputy governor of Sistan-Baluchistan Province, told the official IRNA news agency that the "terrorists" fled back to Pakistan following the attack in the Negur district.
The province has a large Sunni Muslim community and has seen repeated attacks by militants on the security forces of mainly Shi’ite Iran.
The latest clash was reportedly the deadliest since October 2013, when 14 border guards were killed in an attack claimed by the Al-Qaeda-affiliated group Jaish-ul Adl.