The most senior of three British soldiers on trial accused of abusing Iraqi civilians said today that he had tied up one of them because the man had been acting suspiciously.

"I tied him up as best as I could and kept him away from the other three. He seemed to be the ringleader," Corporal Daniel Kenyon said at the soldiers’ court martial in western Germany, as the defence opened its case. "I blindfolded him because it was a hide," (a place where the soldiers had their beds and personal belongings stored) the 33-year-old Royal Fusilier said.

Corporal Kenyon, and lance corporals Mark Cooley and Darren Larkin, are charged with offences ranging from assault to forcing detainees to simulate sexual acts at a vast storage depot near Basra, southern Iraq, in May 2003.

He tied up one civilian because he had been looking at their Warrior armoured vehicle in which a number of weapons were kept, Corporal Kenyon told the court martial at a British barracks in Osnabruck.

Earlier, the military panel acting as a jury heard how the soldier had been given a tour of the walled-in depot, essentially a network of warehouses, and told how to deal with any looters by a Sergeant Major Richard Jackson. Corporal Kenyon said that the sergeant major, who has since left the army, had told him: "We will give them a good kicking and chuck them over the wall."

The corporal, the first of the defendants to take the stand, also said that he was unsure of how to deal with looters, barely two weeks after US President George W. Bush had declared an official end to major hostilities in Iraq.

"Most of the lads including us were not sure what powers there were to stop these things and we were confused how we were meant to deal with the looters," Corporal Kenyon said.

The court martial and British military legal authorities have acknowledged that the attempt to catch the looters, known as Operation Ali Baba, contravened the Geneva Conventions on the treatment of civilians. Under the conventions, civilians cannot be forced to work and must be paid if they accept to carry out any tasks.

In at times confusing testimony, Corporal Kenyon also denied taking a photograph of Lance Corporal Larkin standing on top of one civilian and insisted that he had in fact reprimanded the soldier for his actions.

"I would not have taken a picture with Larkin standing on top of the Iraqi as there was a split second. If we had a video you would have seen what happened next," he said. Lance Corporal Larkin has pleaded guilty to assault for standing on the Iraqi and faces a six-month prison sentence.

Defence lawyers have been trying to establish that the operation was illegal, that the soldiers were ill-informed about their role and that the blame for the abuses lies higher up the military chain of command.

Earlier today, the court martial dropped a charge of conduct prejudicing good military order against Lance Corproal Cooley, 25, for simulating a kick on an unidentified Iraqi civilian. He still faces other charges.

Last week, two charges relating to the sexual humiliation of Iraqi prisoners were also dropped, after a key prosecution witness changed his evidence.

Prosecutors said that they would not proceed with an allegation against Lance Corporal Darren Larkin that he forced captured men to strip moments before they were forced to perform a simulated "sex show".

Lance Corporal Larkin, 30, from Oldham, Greater Manchester, has already admitted assaulting one of the prisoners after he was pictured in his boxer shorts standing on top of him.

A charge against Corporal Daniel Kenyon, 33, from Newcastle upon Tyne, of aiding and abetting Larkin was also dropped last week.

The changes to the charge sheet mean that the panel of seven military officers trying the men is now hearing evidence on seven charges against two soldiers - two against Lance Corporal Cooley and five against Corporal Kenyon.

Both Lance Corporal Cooley and Corporal Kenyon could be jailed for up to two years on each charge if found guilty. The court martial is expected to end this month.

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