The suicide bomber who carried out last week's attack that killed 27 members of Iran's Revolutionary Guards was a Pakistani national, the elite force said on Tuesday.
"The suicide bomber was named Hafez Mohammad-Ali and was from Pakistan," said Brigadier General Mohammad Pakpour, commander of the Guards' ground forces, quoted by the force's Sepah news agency.
The February 13 suicide bombing killed 27 Revolutionary Guards on a bus in the volatile southeastern province of Sistan-Baluchistan which borders Pakistan.
The general said the probe into the attack had made headway after the model of the explosives-packed car that exploded next to the bus had been identified. "Two days ago the first clue, a woman, was identified and arrested, and through this woman, we reached others," Pakpour said.
Apart from the suicide bomber, one of the suspected accomplices was also Pakistani, he said.
Pakpour said the attack had originally been planned for February 11 to coincide with celebrations for the 40th anniversary of Iran's Islamic revolution. But had security forces had been "fully prepared" on that day, he said.
A jihadist group, Jaish al-Adl (Army of Justice), which Tehran says operates mostly out of bases in Pakistan, claimed responsibility for the attack. Iran has Pakistan's army and intelligence agency of sheltering the jihadists.
Jaish al-Adl has been functioning since 2012, after its parent terror outfit Jundullah was dissolved after its leader Abdolmalek Rigi was captured and executed by Iran in 2010.
The attack was one of the deadliest one on the security forces of Iran on Wednesday, days after the country celebrated 40 years of the 1979 Iranian Revolution.
Iran is the second nation to find Pakistan link to a terror attack in the recent past. Last week, terror struck the Pulwama district in India as an IED blast on a 70-vehicle convoy carrying CRPF jawans resulted in 40 of them being martyred. Pakistan-based terror outfit Jaish-e-Mohammad claimed responsibility for the attack