TEHRAN: Gunmen killed five civilians during a “terrorist attack” on a judiciary building in southeast Iran on Saturday before being killed themselves, state media reported.

“Unknown gunmen attacked the judiciary center in Zahedan,” the capital of southeastern Sistan-Baluchistan province, the judiciary’s Mizan Online said.

“Five people have been killed and 13 injured in this terrorist attack,” the report said while adding that the counts are “preliminary” and the toll may rise.

Separately, the official IRNA news agency reported that three of the attackers were killed during the assault, citing the regional headquarters of the Islamic Revolutionary Guard Corps (IRGC).

According to Alireza Daliri, deputy police commander of Sistan-Baluchistan province, the attackers attempted to enter the building disguised as visitors.

The assailants threw a grenade into the building, Daliri said, killing several people inside, including a one-year-old baby and the child’s mother.

Jaish Al-Adl (Arabic for ‘Army of Justice’), a Baloch militant group operating from the borderlands between Iran, Pakistan, and Afghanistan, mainly the Sistan-Balochistan triangle, but active inside Iran, claimed responsibility for the attack.

Located about 1,200 kilometers (745 miles) southeast of the capital Tehran, the restive province shares a long border with Pakistan and Afghanistan.

The area has been the scene of recurring clashes between Iranian security forces, including the IRGC, and rebels from the Baluch minority, radical Sunni groups, and drug traffickers.

In one of the deadliest incidents in the region, ten police officers were killed in October in what authorities also described as a “terrorist” attack.