In its quarterly update to Congress, the Pentagon reported that from Feb. 11 to May 12, as the new Iraqi unity government was being established, insurgents staged an average of more than 600 attacks per week nationwide. From August 2005 to early February, when Iraqis elected a parliament, insurgent attacks averaged about 550 per week; at its lowest point, before the United States handed over sovereignty in the spring of 2004, the attacks averaged about 400 per week.

The vast majority of the attacks -- from crude bombing attempts and shootings to more sophisticated, military-style assaults and suicide attacks -- were targeted at US-led coalition military forces, but the majority of deaths have been of civilians, who are far more vulnerable to insurgent tactics.

``Overall, average weekly attacks during this `Government Transition' period were higher than any of the previous periods," the report states. ``Reasons for the high level of attacks may include terrorist and insurgent attempts to exploit a perceived inability of the Iraqi government to constitute itself effectively, the rise of ethno sectarian attacks . . . and enemy efforts to derail the political process leading to a new government."

As if to underscore the grim report, a spate of violence swept Iraq yesterday. Bombs and other attacks killed 54 people, including an American soldier, according to wire reports. The deadliest bombing, in a popular market in a town about 20 miles north of Baghdad, killed at least 25 people and wounded 65.

On Monday, 40 other people were killed in various attacks, including two CBS journalists who died in a bombing that critically wounded a network correspondent. To date, 2,468 US soldiers have died since the March 2003 invasion, while more than 4,000 Iraqi civilians have died in war-related violence since the beginning of the year, according to government figures and media reports.

The Pentagon report, made public yesterday, contained some positive news, including an opinion poll that indicates most Iraqis don't like the insurgents' use of violence as a political tool. In addition, according to the report, a growing number of Iraqi security forces can operate without US military support, more ethnic groups are represented in the security forces, oil production has remained steady, and more than 10,000 new business registrations have been issued.

But the overall picture of progress in Iraq is grim, dominated by the seemingly ceaseless violence.

Despite military crackdowns on insurgents and the installation of the new Iraq government, the Pentagon wasn't optimistic about quelling the violence in the near future. Officials who briefed reporters on the Iraq assessment cautioned that violence against troops and Iraqi civilians probably won't slow until at least 2007 -- if the unity government exerts more of its own authority and, according to the report, ``addresses key sectarian and political concerns" that fuel the bloodshed.

The 65-page report, compiled by Multi-National Forces Iraq in Baghdad, identified a disturbing trend: New signs that former members of Saddam Hussein's regime who are fighting the American-led coalition and other Iraqis who don't like the new government are collaborating with Al Qaeda operatives and other foreign terrorists who are responsible for some of the deadliest attacks in the country.

The progress report also concluded that militias loyal to Iraq's various ethnic groups are to blame for a steady number of ethnic reprisals touched off by the Feb. 22 bombing of a revered Shi'ite Muslim shrine. The militiamen apparently have also infiltrated the Iraqi Security Forces.

``Individual militia members have been incorporated into the ISF, but the loyalties of some probably still lie, to some extent, with their ethno sectarian leaders," according to the report. ``Shi'ite militias, in particular, seek to place members into Army and police units as a way to serve their interests and gain influence."

Though the sectarian violence has subsided a bit in recent weeks -- and fears of a full-blown civil war have not been realized -- conflict among sects is still far higher than before the February mosque attack, according to the report. More than 1,000 casualties from sectarian violence were reported in February, compared with more than 1,500 in March, and about 1,200 in April, according to the Pentagon report. Before the mosque bombing, which has been blamed on foreign terrorists loyal to Al Qaeda, there were a few hundred sectarian-based attacks per month.

On the positive side, Pentagon officials pointed out that newly-trained Iraqi Security Forces have become more capable, and a growing number of units are leading or playing significant roles in anti-insurgent missions.

``Increasingly, Iraqi Security Forces are taking the lead in operations and primary responsibility for the security of their nation," the report said. ``As of May 15, there were two Iraqi divisions, 16 brigades, and 63 Army and National Police battalions with security lead in their areas of responsibility."

Meanwhile, as of May 6, the Iraqi Ministry of Defense, Ministry of Interior, and Ministry of Finance have assumed control of 34 bases from US-led forces, according to the assessment. Though the Pentagon has acknowledged that Sunni Muslims in particular are not fully represented, the Iraqi security forces are becoming more representative of the country's ethnic breakdown -- Shi'ite, Sunni, Kurd, and other minorities.

The report also outlined growth trends in the Iraq economy and steady political progress, culminating with the establishment of a unity government in Baghdad earlier this month.

For example, the number of independent mass media outlets has steadily grown; new business registrations are up by nearly 10,000 from the more than 20,000 in early 2005; and weekly oil production has remained at more than 2 million barrels per week.

At the same time, polling data has indicated that most Iraqis do not support violence as a political tool -- a sign that support for the insurgency may be falling, officials said. For example, after the Feb. 22 attack on a revered Shi'ite Muslim shrine in Samarra, 96 percent of Iraqis said such attacks were not acceptable. Another poll cited in the Pentagon report showed that 78 percent of Iraqis believed violence was never acceptable.

Meanwhile coalition forces have received more than 4,500 tips per month from average Iraqis about potential insurgent operations, up dramatically from about 400 in March 2005.