With violence spreading in Iraq, it’s worth asking who is behind it. American officials have attributed many of the attacks on Americans, our allies, and innocent Iraqis to an Iraqi Shiite political leader named Muqtada al-Sadr. But more and more information is emerging that makes the case Mr. al-Sadr isn’t acting on his own.

An Italian intelligence agency, Servizio per le Informazioni e la Sicurezza Militare, a unit of the Italian defense ministry, reported to the Italian Parliament yesterday that Mr. al-Sadr receives his orders directly from the office of the Iranian supreme leader, Ayatollah Khamenei. The report says that agents of the Islamic Revolutionary Guards Corps and the Quds special forces have infiltrated Iraq in the past months and have formed and organized Mr. al-Sadr’s al-Mahdi brigade.

The Italian report says the Iranian agents work under the cover of several religious charity organizations in Sadr city in Baghdad and in the Shiite cities of Karbala, Najaf, and Kufa. And it says that Iran is spending $70 million a month to support these front organizations.

The Italian intelligence report echoes an April 3 report of a London-based Arab newspaper, Al-Sharq al-Awsat, which said it had interviewed a former Iranian intelligence official who was in charge of the Iraqi file for Iranian intelligence. The official told the newspaper that the Iranian radio and television networks, press agencies, and some newspapers close to the security organs are fronts through which Quds Corps and Revolutionary Guards intelligence elements enter Iraq. That official also cited the $70 million a month figure.

A senior analyst at the Middle East Media Research Institute, Nimrod Raphaeli, writes of Mr. al-Sadr that Iranian Ayatollahs prepared him as a cleric. Michael Ledeen wrote yesterday in our pages that Mr. al-Sadr “was formally appointed as the head of the Iraqi Hezbollah by leaders of the Iranian Revolutionary Guards.”

Secretary of State Powell, testifying yesterday before a panel of the Senate Appropriations Committee, was asked about Mr. al-Sadr by Senator McConnell, a Republican of Kentucky.”Do you think he’s getting any support from outside the country, like from Iran, for example?”Mr. McConnell asked. “I can’t say that it is not the case,” Mr. Powell replied.

The task for America and its allies in Iraq in the weeks and months ahead will involve not only mopping up Mr. al-Sadr but following the trail of clues and money and influence all the way to Tehran.