BAGHDAD - Amid the acrid smoke and dust, the cries of the injured being dragged out of the rubble, General Adnan Thabit arrived at the Hamra hotel bomb site in sunglasses, pressed fatigues and a crimson beret.

"Well, gentlemen," he said to me and another journalist who had just been blasted out of our rooms by suicide bombers, "this is what happens when terrorists carry out terrorism: a lot of dead, a lot hurt. Now you can see what we are up against."

The general was savouring his moment. His special forces have been accused by the media and others of carrying out the worst human rights abuses against "suspected insurgents" in what is becoming an ever more savage and dirty war.

His tough words came as five American soldiers were killed and another five wounded in a bomb attack in northern Iraq and as fresh violence gripped the country,

Yesterday a roadside bomb in Baiji, 110km north of Baghdad, killed five US Marines, while more than 50 people died in suicide attacks, one targeting the funeral of a Shiite Muslim sheikh.

Behind the daily reports is a far more shadowy struggle, one that involves tortured prisoners huddled in dungeons, death-squad victims with their hands tied behind their backs, often mutilated with knives and electric drills, and families searching for relations who have been "disappeared".

This hidden struggle surfaced last week when US forces and Iraqi police found 169 captives, who looked like Holocaust victims, inside an Interior Ministry building.

The "disappeared" prisoners were being held, it is claimed, by the Shiite Badr militia, which controls part of the ministry. Bayan Jabr, the Interior Minister, is a former Badr commander.

General Adnan's commandos come under the ministry's control. So does the Wolf Brigade, which vies with the commandos for the title of most feared.

Baghdad is a city in the shadow of gunmen. As I left the Hamra to replace what was lost in my bombed room, I had to negotiate checkpoints of the Badr militia, their Shiite enemies, the Mehdi Army of the radical cleric Muqtada al-Sadr, and the Kurdish peshmerga. The Iraqi police and the Government paramilitaries have their own roadblocks.

And there are others: the Shiite Defenders of Khadamiya - set up under Hussein al-Sadr, a cousin of Muqtada - and the Government-backed Tiger and Scorpion brigades. They are accused of arbitrary arrests, intimidation and extra-judicial killings.

The US and Britain, which trained many of the forces involved and still have ultimate responsibility for them, are implicated. American and British forces have played their own part, from the abuses of Abu Ghraib to deaths in British military custody, from the deployment of white phosphorus as a chemical weapon in the assault on Fallujah to the wild use of overwhelming American firepower, which some have called almost as indiscriminate as the killings caused by Sunni insurgents' car bombings.