Image copyright Metropolitan Police Image caption Anis Sardar's conviction for his role in the Iraq insurgency has been hailed as a 'landmark prosecution'

A London black cab driver has been jailed for life with a minimum term of 38 years for the murder of a US soldier in a roadside bombing in Iraq in 2007.

Anis Sardar, 38, from Wembley, built bombs as part of a conspiracy to kill Americans fighting in the country.

One caused the death of 34-year-old Sergeant First Class Randy Johnson, of 2nd Stryker Cavalry Regiment.

Sardar showed no emotion as Judge Mr Justice Globe told him he must be detained for "an extremely long time".

During his trial, Sardar told jurors he had become involved in the Iraqi insurgency to protect his fellow Sunni Muslims from Shia militias.

'Landmines'

But handing down his sentence at Woolwich Crown Court, the judge rejected Sardar's defence that he had been involved just once in bomb-making to protect the Sunni community.

He said: "I am satisfied that at the material time of the offences you had a mindset that made Americans every bit the enemy as Shia militias. Both were in your contemplation at all times."

Mr Justice Globe described the bombs built by Sardar and his co-conspirators as "professionally made" and "in effect landmines".

The judge told Sardar that Sgt Johnson, a family man with two young children, had been described by his commanding officer, Major Eric Adams, as showing "deep compassion" in leading his platoon.

Image copyright US ARMY Image caption Sergeant Randy Johnson died after taking the full blast of a homemade bomb

The judge said: "It is therefore the saddest irony that when the eight-wheel Stryker vehicle containing the American soldiers ran over and exploded an IED it was Sgt First Class Johnson who was killed."

He said the loss of Sgt Johnson, who was awarded the Purple Heart and Bronze Star posthumously, was "one of the sad tragedies in what was going on in Iraq in 2007".

He added: "By the jury's verdict it is a loss for which you are directly responsible."

Prosecutor Max Hill QC read a short message from Sgt Johnson's widow Claudia in which she said: "Thank you so much, it's a big relief to know that justice has been served.

"However, it does not change much for us. Randy will be greatly missed."

Why Anis Sardar was convicted in the UK

Image copyright Julia Quenzler

Analysis: Dominic Casciani, BBC home affairs correspondent

How can a man who helped make bombs in a foreign war end up on trial in a British court?

Sgt Johnson was killed amid the chaos of Iraq, but as far as British detectives and the Crown Prosecution Service were concerned, this was an act of terrorism, rather than an act of war.

In legal terms, he was a British citizen who had committed a crime overseas.

Generally speaking, the criminal law of the land is just that - it applies only to offences in the UK.

But murder is one of a small number of the most serious crimes that are extra-territorial.

Read more from Dominic Casciani here

'Landmark prosecution'

Sardar's conviction in a UK court for his role in the Iraq insurgency was hailed a "landmark prosecution" on Thursday.

Sue Hemming, from the Crown Prosecution Service, said that it showed international borders were "no barrier" to terrorists in the UK being prosecuted for murder committed anywhere in the world.

Sardar was stopped at Heathrow and his fingerprints were taken after he made his way back to the UK some two months after Sgt Johnson was killed.

In 2012, officers who were searching his London home as part of a separate investigation found an Arab language bomb-making manual with references to Islam on a computer disc.

Sardar originally denied to police that he had been "directly or indirectly" involved in bomb-making. But on the second day of his trial he admitted that fingerprints on two of four devices found in or around the road west out of Baghdad and linked to the case were his.

Image copyright PA Image caption US Army Staff Sergeant Mark Aggers, who served as a gunner on the Stryker, gave evidence

Mark Aggers, who was serving as a gunner on the Stryker vehicle, was also left with serious shrapnel wounds, while three further servicemen suffered concussion.

Henry Blaxland QC, for the defence, said that Sardar had moved on from his role in the insurgency.

"He tried to put it behind him but it has come back to haunt him," Mr Blaxland said.

The US-led invasion of Iraq began in 2003, amid claims Iraqi leader Saddam Hussein had weapons of mass destruction. It sparked years of violent conflict with different groups competing for power.

British forces ended combat operations in 2009 and the US did so the following year. A total of 179 UK service personnel and nearly 4,500 US soldiers were killed during the conflict.