04/16/2008 05:12 am ET Updated May 25, 2011

As Petraeus Testifies, Baghdad Teeters On Edge Of Erupting

Army Gen. David Petraeus and Ambassador Ryan Crocker were critical of Iran when they testified Tuesday before the Senate, barely giving credit for an Iranian-brokered cease-fire that curbed the killing after a week of Shiite-on-Shiite bloodshed in southern Iraq and Baghdad.

As they spoke, firebrand Shiite cleric Muqtada al Sadr threatened to unleash his Mahdi Army militia against U.S. and Iraqi forces. Once again, it was Iran that stepped into the political vacuum and urged a halt to militia attacks into the heavily fortified Green Zone, where U.S. and Iraqi officials, including Petraeus and Crocker, have their offices.

The Iranian foreign ministry called for "restraint and prudence of various Iraqi groups," an implicit rebuke of Sadr, who is living and studying in Iran.

The violence began two weeks ago when Iraqi Prime Minister Nouri al Maliki launched an ill-prepared offensive against militias in the southern port city of Basra. It ebbed after a delegation of the Iraqi governing parties traveled to Iran for talks with a top commander of the Qods force of the Iranian Revolutionary Guards.

This week, it transformed into a conflict largely between the Mahdi Army and U.S. forces. Twelve U.S. troops were killed since Sunday, at least eight of them in the capital, several of them from rocket and mortar attacks into the Green Zone.

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