Guilty of war crimes - or victim of a feud with US soldiers?

British officer who won international recognition for speech to troops on eve of Gulf War accused of pistol-whipping an Iraqi civic leader

As he faced accusations of war crimes yesterday, Lieutenant Colonel Tim Collins remained characteristically circumspect. "I am amazed by the allegations, but I understand the need to investigate them thoroughly," he said. "After all, we have gone into Iraq as liberators, and we cannot be accused of the kind of things the old regime was guilty of. That is the right thing to do".

The investigation into Lt Col Collins, for alleged breaches of the Geneva Convention, began after complaints were made against him by an American major. It was the culmination of a series of rows and confrontations between the British commander and some of the US servicemen under his command, including some angry words, ironically, regarding their behaviour towards Iraqis.

Lt Col Collins, 43, who commanded the 1st Battalion of the Royal Irish Rangers, is the first member of the Anglo-American forces to be investigated for civil rights violations during Operation Iraqi Freedom. The widespread and unwelcome publicity it has attracted will be highly embarrassing for the British Government at a time when the allied plans for post-Saddam Iraq appear to be unravelling

The Belfast-born commander is also one of the most high-profile soldiers to have emerged during the war, having sprung to overnight fame for a hugely publicised address to his troops before the war started. The "Agincourt speech", as it was quickly labelled by the media, so impressed the Prince of Wales that he sent the colonel a letter of compliment and President George Bush is said to have ordered a framed copy for the White House.

Lt Col Collins, it is alleged, pistol-whipped an Iraqi "civic leader", gashing his head; punched and kicked prisoners of war; shot the tyres of vehicles when there was no threat to Allied lives; fired on the ground "near the feet" of Iraqi civilians and also spoken to civilians in a "threatening" fashion.

Serious as the accusations are, they do not, despite what Lt Col Collins himself said yesterday, equate to the depredations of Saddam Hussein's dictatorship.

More pertinently, his British colleagues were yesterday comparing them to the actions of the Americans who shot dead unarmed demonstrators in cities such as Mosul and, as western journalists witnessed, killed civilians without provocation at various checkpoints in Baghdad.

So what lies behind the accusations? According to British defence sources there had been friction between the colonel, who revelled in his nickname among the men of "Nails" (as in: "hard as") and US reservists attached to the Royal Irish. He is said to have found them "not up to the mark", especially in their fire control duties, and told them so in his characteristically blunt fashion. He and his officers, all combat veterans, also began to show increasing disquiet about the "Rambo-esque" attitude of the American part-timers and the "needlessly aggressive way" they allegedly behaved towards the locals.

While the row simmered, Lt Col Collins was having a good war, started off by his stirring speech. Prince Charles, in his personal note, said how "profoundly moved" he was by the "extraordinarily stirring, civilised and humane" words. "What you have said somehow encapsulated, in a brilliantly inspired way, everything that we have come to expect of our armed forces and demonstrated why, quite simply, they are the best in the world," the Prince wrote.

The colonel - photogenic, chomping cigars and shooting verbally from the hip - became an instant media star. There were colourful tales of his derring do and how, in his office at the barracks in Canterbury, Kent, he had on his wall a blood splattered G-3 semi-automatic rifle seized from a leader of the West Side Boys militia during the hostage rescue in Sierra Leone two years ago. His repeated, almost evangelical, declaration to reporters that the US and British forces were engaged in a war of liberation was received with approval by the Government.

Lt Col Collins was selected for promotion to full colonel, on a salary of £ 55,000 a year, and has now left the Royal Irish while awaiting his new posting, which was expected to be prestigious. One suggestion was that he would be sent on secondment to the Pentagon.

The Royal Irish were tasked to secure some Iraqi oilfields, and it was at Rumailah about a month and a half ago that the American major made his complaint. The inquiry, under Lt Col Jeremy Green of the Special Investigation Branch of the Ministry of Defence police, started a week later. Officers from the Royal Military Police have interviewed British and American service personnel, as well as some Iraqis. A final report will be sent to the MoD prosecutors' office next month.

A Ministry of Defence spokesman said yesterday: "We can confirm that an investigation is being conducted into allegations that have been made against a British officer who was serving in Iraq. We cannot comment further because of the risk of compromising this investigation."

Yet some of the details of the allegation against Lt Col Collins are already in the public domain, described by newspapers and the man himself. At the end of March, in a town in southern Iraq, he shot out all four tyres of a lorry being used by an Iraqi who had allegedly ignored warnings to stop looting. "What part of 'No' don't you understand?" the British commander bellowed.

In a newspaper interview, Lt Col Collins described a visit to the local Baath Party headquarters. "It's chief, who was Lord God on High in these parts, is now considering his options in a prisoner-of-war cage.

"We knew they were threatening people who co-operated with us so we paid some of them an overnight visit. One man found that a shot through his kitchen floor helped him remember where his weapon was hidden."

The allegations of assault are said to relate to Iraqis captured by the hundreds as the southern cities and towns fell to American and British forces. Soldiers report chaotic scenes with Iraqi soldiers mixed up with civilians, and riots in the "cages" where PoWs were being held. British guards were reported to have used their fists and batons to impose order. There was surprise in defence quarters at suggestions that the commanding officer may have become mixed up in these situations.

In his speech, Lt Col Collins told his troops to be "ferocious in battle and magnanimous in victory ... If someone surrenders to you then remember they have that right in international law and ensure that that one day they go home to their family.

"If you harm the regiment or its history by over-enthusiasm in killing or in cowardice, know it is your family who will suffer. You will be shunned unless your conduct is of the highest," he said.

At the time, the words earned Lt Col Collins international fame. The outcome of the investigation will decide whether they come back to haunt him.