The trial of two men charged with the gruesome murder of a British soldier and who attempted to hack off his head in broad daylight on a London street has began in London.

Michael Adebolajo, 28, and Michael Adebowale, 22, are accused of murdering 25-year-old Lee Rigby as he walked to his barracks in Woolwich, south London, in May this year.

The two defendants, both Britons of Nigerian descent who have asked to be identified by Muslim names in court, deny murder.

As the trial opened at London’s Old Bailey court, prosecutor Richard Whittam said the pair had run Rigby over with a car, knocking him unconscious, before attacking him with knives and a meat cleaver in a “cowardly and callous murder”.

Rigby’s relatives watched from the courtroom as Whittam told the jury of eight women and four men that Adebowale had stabbed and cut the soldier while Adebolajo tried to cut his head off.

They had dragged his body into the middle of the road, Whittam said, because “they wanted members of the public to see the consequence of what can only be described as their barbarous acts”.

One witness, compared Adebolajo’s actions to “a butcher attacking a joint of meat”.

Rigby’s widow Rebecca walked out of the court in tears during the harrowing evidence.

There were gasps from the courtroom as the jury was shown CCTV footage of a car veering onto the pavement and ramming into the soldier.

When the police arrived, Adebolajo ran at a police car waving the meat cleaver and was shot by officers, the prosecutor said.

Adebowale charged at police with a gun, and was also shot.

Adebolajo and Adebowale are further accused of attempting to murder a police officer and conspiracy to murder a police officer. They both deny these charges.

The horrifying murder took place in the middle of the day as a group of schoolchildren were returning from a local library, Whittam told the jury. Members of the public turned them back to avoid the “awful” scene.

The prosecutor said passers-by had shown “bravery and decency” in the aftermath of the attack, with one woman confronting Adebolajo despite the fact that he was still holding the meat cleaver and his hands were covered in blood.

Another woman “went to the lifeless body of Lee Rigby and stroked him to provide some comfort and humanity”, he added.

Adebolajo has asked to be referred to as Mujaahid Abu Hamza in court, while Adebowale wants to be called Ismail Ibn Abdullah.

Both defendants have admitted possession of a firearm with intent to cause violence.

The court was shown CCTV footage of Adebolajo buying a block of kitchen knives and a knife sharpener from a south London branch of the retailer Argos on May 21, the day before the attack.

Rigby, the father of a young son, had joined the British army in 2006 and had served in Afghanistan, the court heard.