Shafaq News/ A senior security official in Iran's Sistan-Baluchestan province was assassinated on Friday in an armed attack by unidentified gunmen, according to Iranian media reports.

The semi-official Mehr News Agency reported that the assailants killed Hossein Biri, the deputy head of the Khash city police security division," near his home after he attended Friday prayers in civilian clothing.

The Pakistan-based Sunni Muslim group Jaish al-Adl (Army of Justice) claimed responsibility for the attack.

Jaish al-Adl, an armed Baluch opposition group, has been a significant force for "national and sectarian rights." The group is designated as a terrorist organization by the Iranian government and several Western nations, including the United States.

Jaish al-Adl emerged in 2012, primarily composed of former members of the Jundallah group, which was weakened after Iran arrested most of its leaders. The group seeks the independence of the Sistan region in eastern Iran and the Baluchistan region in southwestern Pakistan.

Positioning itself as a defender of Sunni rights in Iran, particularly in the Sistan-Baluchestan province, Jaish al-Adl has gained attention for its militant activities.

The Baluch population in Iran, estimated at 4 to 5 million, resides mainly in the eastern and southeastern provinces, where they form the majority in Sistan and Baluchestan, adjacent to Pakistan's Balochistan province.