Updated

The two-month old joint U.S.-Iraqi bid to crush violence in the Iraqi capital did "not meet our overall expectations," as attacks in Baghdad rose by 22 percent in the first three weeks of the Muslim holy month of Ramadan, the U.S. military spokesman said on Thursday.

The spike in violence during the month of fasting was "disheartening" and the Americans were now working with Iraqi authorities to "refocus" security measures, Maj. Gen. William B. Caldwell said.

"In Baghdad, Operation Together Forward has made a difference in the focus areas but has not met our overall expectations in sustaining a reduction in the level of violence," Caldwell said at a weekly news briefing.

The gloomy assessment of the operation, which was set in motion with the deployment of an extra 12,000 U.S. and Iraqi troops on Aug. 7, was issued at a time of perceived tension between the U.S. military and administration and the nearly five-month-old government of Prime Minister Nouri al-Maliki.

CountryWatch: Iraq

Caldwell said, for example, that U.S. forces had been forced to release a captured top organizer for radical Shiite cleric Muqtada al-Sadr on Wednesday, a day after he was detained on suspicion of "illegal" activities.

He said Mazin al-Sa'edi, a top organizer with the Sadr Movement political party in western Baghdad, was set free on the demand of al-Maliki. Al-Sa'edi had been detain along with five of his aides for suspected involvement in Shiite militant violence.

Caldwell also said that U.S. forces had entered the city of Balad as early as last Friday after it got word of the early stages of the sectarian killings that swept through the region an hour's drive of Baghdad for four days and left at least 95 people dead, most of them Shiites.

He said that the control over the city was left in the hands of the Iraqi military, however, and that the Iraqi government had not asked for U.S. assistance. U.S. forces were continuing to patrol the city, which has a major U.S. air base on the outskirts.

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