A Sunni militant group known as Jundallah claimed responsibility for a bomb attack yesterday on a bus carrying Revolutionary Guards in the southeast of Iran that left 18 dead, reports said.
"A few minutes ago a group known as Jundallah [Soldiers of God] headed by Abdolmalek Rigi, one of the rebels of the east of country, claimed responsibility for this terrorist act by issuing a statement," the semi-official Fars news agency said.
The report did not give any further details.
It was not possible to further confirm the claim for the bombing in the city of Zahedan, the capital of Sistan-Baluchestan Province.
Another statement attributed to Jundallah on a Web site said the attack was a "response to the recent executions" of militants found guilty of bombings in the southwestern Khuzestan Province.
Jundallah has been blamed in recent months for a string of armed incidents along Iran's borders with Afghanistan and Pakistan.
The official Islamic Republic News Agency (IRNA) called yesterday's attack a terrorist operation and said the car's occupants fled on motorbikes seconds before the car exploded.
"This blind terrorist operation led to the martyrdom of 18 citizens of Zahedan," IRNA quoted Guards Commander Qasem Rezaei as having said.
State-run television said the bus had been taking the Guards personnel to work when the attack occurred.
Hossein Ali Shahriyari, a lawmaker representing Zahedan, told an open session of the parliament yesterday that "insurgents and drug traffickers" were behind the attack.
Shahriyari called lawless regions in southwestern Pakistan a safe haven for Iranian insurgents and drug traffickers, and called on the government to take up the issue with Islamabad.
"Why doesn't our foreign diplomatic apparatus deal with Pakistan, whose soil has turned into a safe heaven for insurgents?" he asked.
His speech was broadcast live on state-run radio.
Majid Razavi, an Interior Ministry official, said one of those behind the explosion was arrested less than one hour after the attack.
"One of the perpetrators of this morning's explosion was arrested," IRNA quoted Razavi as saying, but it did not elaborate.
The explosion occurred at about 6:30am in Ahmadabad district on the outskirts of Zahedan, IRNA said.
The passenger car stopped in the middle of the road, forcing the bus loaded with Guards to stop, the news agency said.
The occupants then fled as the car exploded.
Zahedan and its surroundings, which lie near Iran's borders with Pakistan and Afghanistan, have been the scene of clashes between police and drug smugglers in the past.
Three small explosions injured two people in Zahedan last June, but yesterday's explosion was the deadliest in years.
The explosion comes at a time of high tension between Iran and the US over insurgents in Iraq the US says are backed by Iran and over Iran's controversial nuclear program.
Unofficial reports have emerged in recent weeks accusing the US of meddling at Iran's borders and provoking ethnic and religious violence to undermine the Iranian government.
However, there have been no official Iranian statements on the allegations nor any evidence to back up the reports.
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