The Beeb's Paul Reynolds on the Haditha massacre, where U.S. Marines are accused of going on a killing spree last November following a roadside bombing. Several factors may have led to the problems there, he finds.

An excerpt:

It is an intensely dangerous place for the Americans, and the battle-weary men of Kilo Company - the unit which included the marines accused of the massacre - had lost a lot of men there.

And they were operating under disturbing circumstances.

Kilo Company's headquarters were three miles north of Haditha, at a vast dam across the Euphrates. It is a big target, because it supplies power to much of southern Iraq.

Four hundred men of the First Marine regiment were based in this decaying rabbit-warren. Conditions were so disgusting, many just moved out.

They set up these unofficial shacks alongside it. Conditions at the dam have been described as "feral".

Oliver Poole is one of the few reporters to have been there, shortly after the alleged massacre. He was shocked by these strange, primitive huts, which lacked even basic hygiene.

"You walked in and the first words were 'F off', and they were ripping pieces of wood apart to feed the fire," he said. "You could see the conditions in which they lived. And they were filthy. It was disgusting."

There seemed to him to be no real discipline.

"The fact that the officers had let conditions deteriorate to the level in which where people living in such basic environment, that says something," he said. "Where were the officers keeping the standards that the US military keeps in the field?"

Blame game

The marines of Kilo Company are now back at Camp Pendleton, in California. But that question of keeping the men under proper control is essential.

"The hardest thing is not necessarily killing someone or shooting someone; it's not killing someone or shooting someone when you're angry," said Paul Rieckhoff of the Iraqi Veterans Campaign.

"When someone in your unit is killed or wounded it's like someone attacked your family. The responsibility then is on one of the squad leaders, platoon leaders, team leaders to hold those guys back."