DUBAI (Reuters) - Iran’s Revolutionary Guards Corps said five of the 12 border guards kidnapped last month by a separatist group on the border with Pakistan had been freed, the semi-official news agency Tasnim reported on Thursday.

“The five ... who were kidnapped in the Mirjaveh border post by the Jaish al-Zolm (Jaish al-Adl) returned home on Wednesday night. They were released after joint efforts made with the Pakistani side,” the Guards said in a statement, Tasnim reported.

The statement provided no information about the remaining seven guards. But an Interior Ministry official told Iran’s ILNA news agency that the others will be freed soon.

The Iranian separatist group Jaish al-Adl said last month it had abducted 12 border guards, which included members of the Guards, on the border with Pakistan in Iran’s southeastern Sistan-Baluchestan province.

The group said it had seized the personnel to avenge the oppression of Sunni Muslims in the area by Iran’s Shi’ite Muslim rulers.

In September, the Guards killed four Sunni militants at a border crossing with Pakistan, including the second-in-command of Jaish al-Adl.

Jaish al-Adl kidnapped five Iranian border guards in 2014, releasing four of them two months later after mediation by local Sunni clerics.

Iran had threatened to hit militant bases in Pakistan unless Islamabad took action to secure its border area, which Tehran says has become a safe haven for anti-Iran groups to operate.