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 yesterday.
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 neighboring country to crack down on them.
Iran on Saturday warned Pakistan that it would "pay a heavy price" for allegedly harbouring the militants.
"Why do Pakistan's army and security body ... give refuge to these anti-revolutionary groups? Pakistan will no doubt pay a high price," Revolutionary Guards chief Major General Mohammad Ali Jafari said in remarks live on state television.
"Just in the past year, six or seven suicide attacks were neutralised but they were able to carry out this one," Jafari told the mourners, who packed a square in the central city of Isfahan and roads leading to it.
"We will avenge the blood of our martyrs from the Saudi and UAE governments and ask the President (Hassan Rouhani) ... to leave our hands free more than ever for reprisal operations," Jafari told the crowd, drawing chants of "Allahu Akbar" (God is Greatest).