Deputy provincial governor Ali Velayatipour said the gunmen, all members of the Ansar al-Furqan group, were killed in the early hours of Sunday, according to official news agency IRNA.
The militants “intended to attack sensitive centres and military and law enforcement bases”, Velayatipour said.
Iran has designated Ansar al-Furqan a “terrorist” organisation. Last year, the group claimed a suicide attack that killed a police officer, also in Sistan-Baluchistan.
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he province which borders Pakistan and Afghanistan is one of Iran’s poorest, and a frequent scene of clashes between security forces and Baluch minority rebels.
It is home to a large Baloch population, most of whom are Sunni Muslims, in contrast to Iran’s Shiite majority.
On Saturday, gunmen killed a police officer in a shootout in the province, with the Sunni militant group Jaish al-Adl (Army of Justice) claiming responsibility.
The group, based across the border in Pakistan, has claimed multiple attacks in recent years, including an assault on a courthouse last month that left at least six people dead.