Basra in late 2003 was a city falling apart at the seams as over-stretched British soldiers tried to fill the vacuum left by the collapse of Saddam Hussein's police state.

Despite huge controversy over the legality and morality of the war, the US-led invasion of Iraq toppled the dictator more quickly and with less bloodshed than many critics had predicted.

But too little thought had been given to who would run the country after Saddam's overthrow in April 2003, and public services from policing to the emptying of bins collapsed almost overnight.

British troops sent to the sprawling southern city of Basra had been trained for fighting but found themselves having to maintain law and order as they struggled to deal with a restless population and a growing insurgency.

Looting was rife and the relatively relaxed atmosphere of the period straight after the invasion, when UK forces donned soft berets to demonstrate their intentions were friendly, soon gave way to ugly tensions and mutual suspicion between Iraqis and their occupiers.

This was the background to the deployment of the Preston-based 1st Battalion the Queen's Lancashire Regiment (1QLR) to Basra in June 2003.

Tempers boiled over as the city sweltered during the stiflingly hot summer months and severe shortages of electricity and fuel meant most people had to do without air conditioning.

British soldiers had to deal with everything from Iraqi children throwing stones at their vehicles to full-scale riots and road blocks made from burning tyres and cars.

The situation in Basra deteriorated in August 2003 with the murders of 1QLR officer Captain David "Dai" Jones, who was blown up by a roadside bomb while travelling in a military ambulance, and three members of the Royal Military Police (RMP) killed when gunmen opened fire on their civilian jeep.

These killings of popular comrades hardened the attitudes of UK forces and led to a crackdown on suspected insurgents in the city.

Operation Salerno, launched in the early hours of Sunday September 14 2003, saw 1QLR soldiers searching hotels in Basra for Iranian militants and Iraqis loyal to Saddam's regime.

One of the hotels they raided was the Ibn Al Haitham, where 26-year-old father-of-two Baha Mousa was working as an overnight receptionist.

After finding weapons, fake ID cards and military clothing, the British troops arrested Mr Mousa and nine other Iraqi men and took them back to their base.

Some members of 1QLR believed - incorrectly - that the men in custody were linked to the deaths of Capt Jones and the RMP soldiers, and this in part explains the severity of the humiliating abuse meted out on the prisoners.

The Iraqi detainees said they were beaten, kicked, sworn at, forced to scream in an orchestrated "choir", urinated on and had their heads flushed down a toilet.

They also suffered five interrogation techniques specifically outlawed by the British Government in 1972: hooding, sleep deprivation, being denied food and drink, being subjected to white noise and being made to stand in painful "stress positions".

Mr Mousa died after being hooded for nearly 24 of the 36 hours he spent in custody, and some of the men held with him suffered serious injuries as a result of their ordeal.

The public inquiry heard that there was confusion among Army officers and their men about what methods they were legally allowed to use on detainees.

Shortly after the March 2003 invasion of Iraq, the International Committee of the Red Cross (ICRC) complained to the British military about prisoners being hooded, left in the sun and possibly put in stress positions.

UK commanders issued orders banning hooding in May 2003 and October 2003, but the practice continued to be used until the following May.

Four months before Mr Mousa's death, then-armed forces minister Adam Ingram wrote to Labour MP Michael Foster: "There were a small number of occasions at the start of the conflict where prisoners were hooded for short periods - this practice has now been stopped."

Seven 1QLR soldiers, including the battalion's former commanding officer, Colonel Jorge Mendonca, faced allegations relating to the mistreatment of Mr Mousa and the other Iraqi detainees at a high-profile court martial in 2006/07.

But the trial ended with them all cleared, apart from Corporal Donald Payne who became the first member of the British armed forces convicted of a war crime when he pleaded guilty to inhumanely treating civilians.

Col Mendonca retired from the Army soon after the court martial, saying he felt he had been "hung out to dry", but the inquiry heard claims he was "gung-ho" and "trigger happy" when dealing with suspected insurgents in Iraq in 2003.

The Ministry of Defence (MoD) agreed in July 2008 to pay £2.83 million in compensation to the families of Mr Mousa and nine other Iraqi men abused by British soldiers.

Meanwhile, the MoD continues to face legal action over claims that more than 100 other Iraqis suffered ill-treatment at the hands of UK troops during the 2003 to 2009 conflict.

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