Iranian President Mahmoud Ahmadinejad has accused Pakistani agents of being involved in a suicide attack that targeted a group of elite Revolutionary Guards in southeast Iran Sunday that killed at least 35 people. A Pakistani spokesman condemned the attack, which is thought to be the work of the Sunni resistance group Jundullah. He refuted the claim that Jundullah's leader is in Pakistan. "We were informed that some security agents in Pakistan are co-operating with the main elements of this terrorist incident," Ahmadinejad said to the state’s semi-official Fars news agency. He demanded the criminals from Pakistan, and said Pakistan must apprehend those who planned the attack and shouldn’t allow terrorists to use its land. Earlier, an Iranian official blamed "U.S. action" for contributing to the attack. Jundallah says it's fighting against the political oppression of Iran's Sunni minority. Five Revolutionary Guards were killed by the bomb, and the group has vowed revenge.