A soldier on home leave from Bosnia slashed a stranger's throat then killed the man's cousin by plunging the weapon into his chest, following a petty argument in a burger bar, a court heard.

Soldier David Tillen was in the centre of Sunderland with his younger sister and another girl last December 28, when an argument broke out in the Burger King outlet in the city's main railway station.

The 26-year-old is alleged to have slashed Graham Scott across the throat, severing his windpipe. It is claimed he was then chased along the street by Mr Scott's cousin, Steven Gibbon, who he stabbed three times, including once just below his throat, severing a major artery.

Tillen, of Witherwack, Sunderland, Tyne and Wear, appearing at Newcastle Crown Court, has denied murder and wounding with intent.

Yesterday, the court heard how Tillen and the two girls had asked to use the toilet in Burger King, but were refused. While Tillen was arguing with staff, Mr Scott, his girlfriend and Mr Gibbon walked in.

Following words between them, Tillen lashed out at Mr Scott, 22, of Sunderland, and slashed his throat before leaving the burger bar, it is claimed.

He was then chased by 21-year-old Mr Gibbon, also of Sunderland, who jumped on his back, and during that fight Tillen is alleged to have murdered him before throwing the knife in a bin and fleeing.

When interviewed by police, Tillen, who the court heard was on home leave from Bosnia because his girlfriend's son had died, told detectives he had initially pulled out a multi-piece utility tool to frighten the two men off. He said that Gibbon had been carrying a knife when he jumped on his back and he had only lashed out while trying to fend him off.

John Milford QC, prosecuting, said: ''The weapon he used was somewhat unusual, it was a Leather Man Tool.

He said of Mr Gibbon: ''The fatal injury was high on the centre of his chest. It penetrated three inches and severed an artery in his neck. It would not have been survivable.

''Mr Scott's girlfriend, who had been looking after him in Burger King, left to see what had happened to Mr Gibbon and found him lying on the pavement, mortally wounded.''

The jury was expected to be shown CCTV camera footage of the parties inside Burger King. The trial is expected to last seven days.