Iraqi officials said Thursday that multinational forces detained five Iranians in an overnight raid on Teheran's diplomatic mission in the northern city of Irbil. The forces stormed the building at about 3 a.m., detaining the five staffers and confiscating computers and documents, two senior local Kurdish officials said, speaking on condition of anonymity because of the sensitivity of the information. Irbil is a city in the Kurdish-controlled north, 350 kilometers from Baghdad. A resident living near the mission said the foreign force used stun bombs in the raid and brought down an Iranian flag that was on the roof of the two-story yellow house. As the operation went on, two helicopters flew overhead, said the resident on condition of anonymity because he feared retribution. "They took five Iranians with them and at about 7 in the morning they handed over the house to Kurdish peshmergas," he said. In the early afternoon, a number of Kurdish guerrillas could be seen around the building preventing people from getting close to the house and not allowing cameramen and photographers to take pictures. The report, which first appeared on Iraq state television, also was confirmed by a Shi'ite official in the capital, who declined to be named for the same reason. The US military issued a statement saying it had taken six people into custody in the Irbil region but made no mention of a raid on the Iranian consulate. It declined further comment on the raid. The Iranian embassy in Baghdad has sent a letter of protest to the Iraqi Foreign Ministry for the illegal move, and has called on the Iraqi government to help obtain the immediate release of its five detained staff, the Iranian IRNA news agency reported. The motive for the raid was not known, but it came as tensions are high between Iran and the United States. The Bush administration has accused Iran of seeking to develop nuclear weapons and of helping fuel violence in Iraq. Iranian President Mahmoud Ahmadinejad, meanwhile, is trying to expand Iran's role in Iraq as a counter to US influence in the Gulf region. Late last month, US troops elsewhere in Iraq detained at least two Iranians and released two others who had diplomatic immunity.