At least nine including three gunmen killed in 'terrorist' attack in southeast Iran

• Attackers attempted to enter building disguised as visitors.
• 22 also injured in courthouse attack, say police.
• Mother, child were among those killed in attack.
  

At least six people, including law enforcement, were killed Saturday during a "terrorist attack" on a judicial building in southeast Iran, the judiciary said.

"The number of martyrs increased to six," the judiciary's Mizan online said following earlier reports of a death toll of five, with 13 injured.

Provincial chief justice Ali Movahedi-Rad, cited by Mizan, later announced the injured count had reached 22,"most of whom were civilians".

All three of the gunmen, who had tried to enter the building disguised as visitors and were wearing explosive vests, were killed, he added.

"Three of the terrorists have been killed according to the announcement of the Quds Headquarters of the Islamic Revolutionary Guard Corps," Movahedi-Rad said.

The death toll also included three law enforcement members who were protecting the courthouse.

According to Alireza Daliri, deputy police commander of Sistan-Baluchistan province, the assailants threw a grenade into the building, killing several people inside.

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

In one of the deadliest incidents in the region, 10 police officers were killed in October in what authorities also described as a "terrorist" attack.