The vehicle of Mohammad-Reza Shahouzehi, a tribal elder of the Shahouzehi clan, came under fire by armed militants while he was inspecting the area under his jurisdiction near Eskalabad, close to Dehpabid in Sistan and Baluchestan province, the Quds base of the IRGC Ground Forces said.
Two of his companions, identified as Esmail Shavarzi and Mokhtar Shahouzehi, were seriously wounded in the attack and later died from their injuries, the IRGC said in its statement, calling it an act of terrorism.
The killing follows several similar incidents in recent months, mostly claimed by the Sunni militant group Jaish ul-Adl, designated as a terrorist organization by both Iran and the United States.
In September, Reza Azarkish, a local Basij militia member, was shot dead in Iranshahr. Earlier in the month, Iraj Shams Askani, a member of the Revolutionary Guards, was gunned down by Jaish ul-Adl in the border town of Rask.
Last month, Parviz Kadkhodaei, a local Basij commander in Nikshahr, was killed in a separate assault. Prominent tribal leader Mullah Kamal Salahi-zehi was also killed in October when unidentified gunmen opened fire on his vehicle in Iranshahr.
The province, bordering Pakistan and Afghanistan, has long been the scene of attacks by Sunni insurgent groups that Tehran says are backed by foreign intelligence services.