British troops in tanks and helicopters stormed an Iraqi jail last night to rescue two soldiers who were arrested after allegedly killing a policeman and wounding another, the governor of Basra said.

The two men had been taken to the Basra jail after violence erupted yesterday in the southern Iraqi city.

Photographs of the two - thought to be special forces officers - were taken and released to the media.

One of the men had his head swathed in bandages and appeared to have bloodstains on his top. The other, who apparently had blood smeared on his trousers, had plasters on his head.

British troops had arrived at the police station where the two men were being held and encircled the building.

They were attacked by demonstrators hurling rocks and petrol bombs.

During the mele, one soldier was seen engulfed by flames scrambling from his tank and gunfire was exchanged between the two sides.

According to Ministry of Defence officials in London, three British soldiers were hurt during the violence, but a spokesman said none of their injuries were life-threatening.

Later, more than ten tanks broke down the walls of the jail and helicopters were used in the rescue operation to release the two servicemen.

It was also reported that 150 Iraqi prisoners escaped in what Mohammed al-Waili, the governor of Basra, described as a "barbaric, savage and irresponsible" act.

The MoD refused to comment after officials said that the two men were undercover officers dressed as Arabs.

The spokesman said: "We can only confirm that the two military personnel have been released."

A defence source said: "It is not our understanding that this was a storming of the prison to release them."

Mr al-Waili said: "A British force of more than ten tanks backed by helicopters attacked the central jail and destroyed it. This is an irresponsible act."

He said the British force had taken the prisoners to an unknown location.

Tensions have been running high in the city since the arrest of a senior figure in the Shia Mehdi Army by UK troops.

In a statement, Defence Secretary John Reid said: ''I can confirm that the two British service personnel detained yesterday by the Iraqi Police Service have now been released and are back with British forces in Multi-National Division (South East).

''The British servicemen, who were seen being injured in the fighting, are being treated for minor injuries only and are expected to return to duty shortly.

''We remain committed to helping the Iraqi government for as long as they judge that a coalition presence is necessary to provide security."