A militant Sunni Muslim group, Jaish al Adl (Army of Justice), which says it seeks greater rights and better living conditions for the ethnic minority Baluchis, has claimed responsibility for the attack
Iranian President Hassan Rouhani blamed the United States and its regional allies on Thursday for a suicide bombing in south eastern Iran that killed 27 members of the country's elite Revolutionary Guards, Iranian state TV reported.
The force said on Wednesday a suicide bomber driving a vehicle laden with explosives had attacked a bus transporting members of the Guards in the province of Sistan-Baluchestan.
A militant Sunni Muslim group, Jaish al Adl (Army of Justice), which says it seeks greater rights and better living conditions for the ethnic minority Baluchis, has claimed responsibility for the attack, Iranian media have reported.
"The crime will remain as a 'dirty stain' in the black record of the main supporters of terrorism in the White House, Tel Aviv and their regional agents," Rouhani said.
Apart from Israel, Rouhani did not name the regional states he believed were to blame. Mainly Shi'ite Muslim Iran does not recognise Israel, which is a key US ally in the region and sees Tehran as posing an existential threat to its existence.
"There is a link between this crime and some regional and international spying and intelligence agencies," TV quoted Iran's top authority, Supreme Leader Ayatollah Ali Khamenei, as saying.
Khamenei ordered immediate action against those responsible for the attack.
In the past, Tehran has accused its main regional rival Saudi Arabia of backing Sunni militia groups who have carried out bloody attacks against Iranian security forces. Riyadh has denied the charges.
Repeating warnings made by senior commanders of the Guards, Rouhani said Iran was determined to bring justice to those responsible for one of the worst assaults ever against the Revolutionary Guards in years.
The assault, which wounded at least 13 people, took place in the province of Sistan-Baluchestan, which has a large, mainly Sunni Muslim, ethnic Baluchi community, which straddles the border with Pakistan.
Jaish al Adl has carried out attacks against the border guards from Pakistan since its founding in 2012. Iran has called on neighbouring countries to crack down on separatist groups.