Iran has summoned the Pakistani ambassador to protest about a suicide bombing that killed 27 of its elite Revolutionary Guards near the border earlier this week, the semi-official Tasnim news agency reported on Sunday.

The Sunni group Jaish al Adl (Army of Justice), which says it seeks greater rights and better living conditions for the ethnic minority Baluchis, claimed responsibility for the attack on Wednesday.

Iran says militant groups operate from safe havens in Pakistan and have repeatedly called on the neighbouring country to crack down on them.