Pakistani officials have announced the arrests of three Iranians in
connection with a suicide attack last month in southeastern Iran that
killed 42 people.
Security officials say the suspects were arrested Thursday in Pakistan's Balochistan province on the Iranian border.
A Sunni rebel group that operates in Pakistan, Jundollah (God's Soldiers), has claimed responsibility for the attack in Iran's Sistan-Baluchistan province.
Iranian officials have accused Pakistan of supporting the rebel group, raising tensions between the two neighbors. But Pakistan condemned last month's bombing, denied any involvement and vowed to help Iran track down those responsible.
Fifteen members of Iran's elite Revolutionary Guard were among those killed in the attack, including several top commanders.
After the bombing, Iran's Revolutionary Guards chief, General Mohammad Ali Jafari, vowed to "retaliate" against U.S. and British intelligence agencies that he said helped the bombers.
The U.S. and British governments condemned the attack and have denied any involvement.
Iranian President Mahmoud Ahmadinejad said although Iran and Pakistan have a "brotherly relationship," the presence of what he called "terrorist elements" in Pakistan is unjustifiable.
The bomber in the attack blew himself up at a sports complex in the Iranian town of Pisheen where the Revolutionary Guards were preparing to meet Shi'ite and Sunni tribal leaders.
Among those killed were tribal leaders, the Revolutionary Guards' deputy commander General, Noor Ali Shooshtari, and the Guards' top commander in Sistan-Baluchestan Rajab, Ali Mohammad-Zadeh.
Some information for this report was provided by AP and Reuters.