Here it goes again:

BAGHDAD, Dec. 24 — The American military is holding at least four Iranians in Iraq, including men the Bush administration called senior military officials, who were seized in a pair of raids late last week aimed at people suspected of conducting attacks on Iraqi security forces, according to senior Iraqi and American officials in Baghdad and Washington.

The Bush administration made no public announcement of the politically delicate seizure of the Iranians, though in response to specific questions the White House confirmed Sunday that the Iranians were in custody. [...]

The action comes at a moment of extraordinary tension in the three-way relationship between the United States, Iran and Iraq. On Saturday, even as American officials were trying to determine the identity of some of the Iranians, the United Nations Security Council passed a resolution imposing mild sanctions against Iran for its refusal to suspend uranium enrichment. Meanwhile, the Bush administration has rejected pressure to open talks with Iran about its actions in Iraq.

Much about the raids and the identities of the Iranians remained unclear on Sunday. American officials offered few details. They said that an investigation was under way and that they wanted to give the Iraqi government time to figure out its position. A Bush administration official said the Iranian military officials held in custody were suspected of being members of the Quds force of the Iranian Revolutionary Guard Corps. It has been involved in training members of Hezbollah and other groups that the Americans regard as terrorist organizations.

American and Iraqi officials have long accused Iran of interfering in this country’s internal affairs, but have rarely produced evidence. The administration presented last week’s arrests as a potential confirmation of the link. Mr. Johndroe said, “We suspect this event validates our claims about Iranian meddling, but we want to finish our investigation of the detained Iranians before characterizing their activities.”

He added: “We will be better able to explain what this means about the larger picture after we finish our investigation.”