Iraqi civilians killed during unrest in Basra could not have been hit by the shots fired by UK soldiers, British Army sources have told BBC News.
Calm has been restored in the southern Iraqi city following unrest after a British Lynx helicopter crashed there.
Five local people - including two children - are believed to have died in the fighting that followed.
British investigators are examining the helicopter's wreckage to find out if it was shot down, as some reports claim.
They removed the remains of the craft and a number of bodies from the crash site on Sunday.
The BBC's Paul Wood visited the crash site and said most Iraqis were friendly and many said they were sorry the helicopter had been shot down.
Our correspondent says the Iraqi authorities are now co-operating with the multi-national forces in Basra.
British commanders say it is another sign of hope and a sign that the exit strategy for Iraq remains on track.
Defence Secretary Des Browne said up to five servicemen died in the helicopter crash. He offered his sympathies to the families of those who died.
He will make a statement to the House of Commons about the incident on Monday.
On the same day, the Ministry of Defence will release the identities of the servicemen who were killed.
British ministers have said it is unclear why the craft went down.
But if enemy fire is confirmed as the cause of the crash, it would be the first time a British military helicopter has been shot down in the area.
The Iraqi president, Jalal Talabani, has sent a message of condolence to UK Prime Minister Tony Blair saying the apparent shooting down was a "hideous crime against the British".
Meanwhile, British and Iraqi forces are investigating how events unfolded when troops clashed with locals after the crash.
The British Army has said the reported civilian casualties are likely to have been inflicted by shots fired at UK troops by militants.
Civilians could also have been injured by a militant mortar attack, Army sources added, but there has been no independent confirmation.
British soldiers who went to the crash scene said they came under small arms and mortar fire before firing live rounds in return, said BBC defence correspondent Paul Wood.
Commanders said some British soldiers had been slightly hurt in the rioting.
Gen John Cooper, commander of the British forces in Iraq, said troops did not fire directly into the crowds but fired live rounds at targets threatening them.
The disturbances were a reaction to a violent incident and that "these things happen", he said, adding that it was soon brought under control by the Iraqi security forces.
The southern Iraqi city was placed under a night-time curfew to defuse tensions.
British troops dismantled their security cordon around the crash site on Sunday, but Iraqi security forces maintained a heavy presence throughout the city.
Mr Browne said about 200 to 300 people "involved in serious disorder were brought under control within a matter of hours and calm and order restored by [Saturday] evening".
The MoD said the Lynx helicopter had been fitted with anti-missile equipment, including flares to confuse heat-seeking missiles and electronic warning and jamming devices.
The Army Lynx has a flight crew of two, a door gunner and can carry a further 10 soldiers.
BBC correspondents in Iraq said the recent events opened a new chapter for British forces in the area - and that it would be increasingly difficult for them to control Basra's streets.
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