An Iranian officer accused of smuggling powerful roadside bombs into Iraq was arrested Thursday in northern Iraq, the U.S. military said.
The arrest could add to tensions between Washington and Tehran already strained by the detention of each other's citizens as well as U.S. accusations of Iranian involvement in Iraq's violence and Iran's disputed nuclear program.
The military said the suspect was a member of the Quds force - an elite unit of Iran's Revolutionary Guards - and was seized from a hotel in the Kurdish city of Sulaimaniyah.
Two other Iranians were detained in the raid but later released, a Kurdish official said.
The Iranian officer was allegedly involved in transporting roadside bombs, including armor-piercing explosively formed penetrators, or EFPs, into Iraq, according to a military statement. It said intelligence reports also indicated he was involved in the infiltration and training of foreign fighters in Iraq.
At the Pentagon, spokesman Bryan Whitman said the arrest was consistent with U.S. policy and that the Iranian posed a serious threat. "It's a further reflection that they've not ceased those activities that we find troublesome," Whitman said.
Officials have said the Bush administration is expected to soon blacklist the Quds force as a terrorist organization, subjecting part of Iran's vast military operation to financial sanctions. The move would be in response to Iranian actions in Iraq and elsewhere.
Iran has denied allegations that it is stoking the violence.