Iraqi Foreign Minister Hoshyar Zebari says the building targeted in a U.S. raid early Thursday was a liaison office that was in the process of becoming an Iranian consulate.

Zebari said Friday that the office had operated in Irbil, in Iraq's Kurdish-controlled north, for a decade.

Coalition troops raided the building in a pre-dawn operation Thursday. The U.S. military says six people were detained for alleged ties to activities targeting troops in Iraq. It says one of the six has been released.

The operation drew protests from the regional Kurdish government and Iran. Russia today said the raid was unacceptable.

The United States accuses Iran of providing material support to the insurgents in Iraq, and allowing terrorists to use Iranian territory to cross in and out of Iraq.