TEHRAN (Reuters) - Iran has threatened the United States with possible legal action for detaining five of its officials for up to 30 months in Iraq.
The five Iranians were given a hero's welcome home on July 12 after their release last week, waving and smiling as they stepped from their plane at Tehran's Mehrabad airport to be met by their families.
Foreign Minister Manuchehr Mottaki, who was also there to greet them, denounced their detention as "inhumane.”
U.S. forces accused some of the detained Iranians arming Shi'ite Muslim militias at the height of Iraq's sectarian war.
The capture of the Iranians stoked tensions between Tehran and Washington, also at odds over Iran's nuclear program.
They were first handed over by their U.S. jailers to Iraq's Shi'ite Muslim-led government, which is friendly with Iran, and transferred to Iran's Baghdad embassy on July 9.
Iran says the detainees are diplomats who were held contrary to international law.
"We reserve the right to legally pursue...this action by the [George W.] Bush government," Mottaki said on state television, adding that they had remained detained after U.S. President Barack Obama took office in January.
One of the freed Iranians sat with his young daughter on his lap as other family members chanted "Death to America," state media reported.
Iranian television last week said three of the men were detained in a 2007 U.S. raid in Iraq's northern city of Irbil, while the two others were "kidnapped" elsewhere in Iraq.
"We hope that the [U.S.] measure will be followed up at the United Nations and other relevant bodies," Mottaki said in comments translated by Iran's English-language Press TV.
Foreign Ministry spokesman Hassan Qashqavi told the semi-official Mehr News Agency that the officials' release would not have an impact on Tehran's relations with Washington.
The White House has said it handed over the Iranians at the request of the government in Baghdad, in compliance with a U.S.-Iraq security agreement that took effect in January.
Under the pact, the United States must gradually transfer more than 10,000 detainees it still holds to the Iraqi government to be either charged in local courts or released.
Obama has been trying to improve ties, offering a new beginning in ties if Iran "unclenches its fist."
But last month's disputed presidential election in Iran has again frayed relations, with Iranian officials accusing the United States and Britain of interfering in its affairs.
The Iranians were detained in Irbil on suspicion of being members of the Iranian Revolutionary Guards' elite Qods Force, which the United States says backs terrorists.
Washington has long accused Iran of fomenting violence in Iraq by arming, funding, and training Shi'ite groups and tasking them with attacking U.S. troops or Sunni Muslim targets.
Iran rejects the charge and says the United States is to blame for the sectarian and insurgent violence that almost tore Iraq apart after the 2003 U.S.-led invasion.