A Sunni group calling itself the "soldiers of God", with alleged links to al-Qa'ida, has claimed responsibility for the bombing of a military bus in which at least 11 people were killed in a lawless region of Iran close to Pakistan and Afghanistan.
The explosion yesterday spurred fears of ethnic and sectarian conflict in the mostly Shia Muslim country. Five men carried out the attack, using a car bomb that was detonated as the bus drove past. One was killed while the others escaped on motorbikes. Reports from the provincial capital, Zahedan, where the attack took place, said five men had been arrested.
Pictures showed the bus scorched and twisted by the side of the road. It was used to transport members of the Islamic Revolutionary Guard Corps, Iran's strongest military force, to and from work. Another 31 people were injured.
The group, known by its Persian name Jundollah, shot dead 12 people last May on the Kerman to Bam highway in south-east Iran. Earlier, the group issued a video showing the execution of an Iranian officer. Other kidnapped soldiers have been beheaded.
The US has in the past accused Iran of sheltering senior al-Qa'ida officials, including Osama bin Laden's son Saad. Iran denies those charges and says Jundollah is itself part of the al-Qa'ida network and is intent on fomenting sectarian strife.
Its leader, Abdolmalek Rigi, is a Baluchi, an ethnic group from the south-eastern corner of Iran.
Shia clerics quickly appeared on television yesterday to say that Sunnis should not be blamed for the bloodshed. Senior Iranian figures have been warning against heightened Shia-Sunni tensions.
"People should face this crime with patience, awareness and realism just like other events and separate the issue of a few rebels from Sunnis - though they were Sunnis - because our Sunni brothers are innocent of these crimes," said Abbasali Soleimani, the regional representative of the Supreme Leader, Ayatollah Ali Khamenei. He added that the perpetrators had not come from inside Iran.
Official figures put Iran's Sunni population at 9 per cent but some independent demographers say it is higher. Sunnis, including Kurds from the west, Turkomans from the north and Baluchis, find it difficult to reach high positions in the Islamic republic, where authority rests with Shia clerics.
Sporadic episodes of unrest in Arab and Kurdish areas to the west over the past three years have been rapidly quelled by the authorities, who fear they are being fuelled by British and US forces in the Middle East. Rights groups have protested against the execution of Arabs held to be responsible for a series of explosions in the south-west last year.
The arid plains and low mountain ranges of Sistan-Baluchistan make up a largely lawless region where bandits and drug smugglers fight pitched battles with Iranian soldiers. Porous borders and tribal ties often allow them to escape into Afghanistan or Pakistan.
In the neighbouring Pakistani province of Balochistan, secessionists have been carrying out attacks. Police have been killed and gas pipelines blown up. A US under-secretary of state, Nicholas Burns, said last month that the Afghan Taliban movement had set up training camps in the Pakistani province.
Since the 1979 revolution, more than 3,300 Iranian soldiers have been killed fighting heroin smugglers, who use Iran as a main route between Afghan poppy fields and Europe. The trade has fuelled a heroin epidemic in Iran, with the number of injecting users said to be more than 200,000.Reuse content