LONDON (Reuters) - Four of the Iranian border guards kidnapped last year by a Sunni militant group on the border with Pakistan were released on Wednesday, the Iranian foreign ministry spokesman said.

Spokesman Bahram Qasemi thanked the Pakistani government for its efforts to facilitate the release of the guards, the semi-official Fars news agency reported.

The militant group Jaish al-Adl abducted 12 border guards in October on the border with Pakistan in Iran’s southeastern Sistan-Baluchestan province. Five of the guards were released in November.

Jaish al-Adl (Army of Justice), which says it seeks greater rights and better living conditions for the ethnic minority Baluchis, claimed responsibility for a suicide bomb attack in February that killed 27 members of Revolutionary Guards.

Iran’s Shi’ite Muslim authorities say militant groups operate from safe havens in Pakistan and have repeatedly called on the neighboring country to crack down on them.

Pakistan has rejected allegations by Iranian officials that it is harboring the armed group, calling them “baseless and completely false”.

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

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