Violent teen murdered man with hunting knife after being released on bail following Portobello attack

A violent youth who slashed a teenager with a blade was freed on bail before murdering a man in a further knife attack.

The armed killer lay in wait for John McNab before chasing him and striking him again and again with a knife at Great Junction Street, in Leith, Edinburgh, on September 2 last year.

Mr McNab, 22, pleaded with his attacker before the murder, saying: “Please, please don’t. I haven’t done anything.”

The murderer messaged a friend after the fatal attack saying: “Ran after him on the middle of Junction Street wi a big Rambo, he fell to the groon and I started stabbing f*** oot o him.”

Enhanced CCTV footage of the vicious attack on Mr McNab was played at the High Court in Edinburgh, prompting some of the victim’s friends and family to leave the courtroom. Many of them were wearing T-shirts in memory of the victim.

The 17-year-old youth, who cannot be identified because of his age, carried out an earlier attack with a knife on March 21, 2025, at the promenade at the city’s Portobello beach when he pursued a 16-year-old boy and seriously wounded him.

Following the knife attack on the teenager, he was released on bail by a sheriff at the city’s Sheriff Court on April 25.

The youth, who is detained at a secure unit, admitted murdering Mr McNab by repeatedly striking him with a knife and assaulting the teenager in the Portobello attack to his severe injury by repeatedly striking him with a knife.

Advocate depute Michelle Brannagan said that before the murder, Mr McNab was socialising with friends.

During the evening, a meeting was arranged for the youth to buy cannabis from a friend of Mr McNab.

The teenager turned up at the meeting wearing a balaclava, covering his face. He produced cash to buy the drugs, but a disagreement arose, and one of Mr McNab’s friends ripped up the notes and slapped him.

He was also punched in the face.

The prosecutor said: “John McNab played no part in the exchange.”

Mr McNab and his three friends walked off, but were followed by the youth, who was aged 16 at the time, shouting: “F***ing come here.”

The group felt threatened and ran to a flat where they locked the door, but when they looked out saw the accused standing outside.

Mr McNab messaged his girlfriend telling her they “just got chased with a samurai sword” and named the teenager as the one who pulled out a sword.

The youth remained in the vicinity of the flat and at one stage smashed a window at the property. He was heard shouting “come on then” and took a large knife in a sheath out of a rucksack.

He climbed into the bushes and remained there until Mr McNab left the flat. When the victim came out to the street, he emerged from the bushes, still with his face covered with a balaclava and ran towards him.

Mr McNab tried to run off when he saw the armed teenager, who pursued him until he stopped and pleaded with him. The teenager told him to shut up, before Mr McNab fell beside a traffic island in the street.

Ms Brannagan said: “A resident in the area overheard the disturbance and described a distressed male shouting ‘please don’t’. He heard what he thought was someone tripping and a thud.”

“On looking out of his window, he saw Mr McNab lying on the ground near the pedestrian crossing, with a person dressed in black, their hood up, lunging down towards the male on the ground as though punching the left side of his abdomen,” she said.

The knife attacker ran off, and Mr McNab managed to briefly get to his feet. He repeatedly called out for help before falling to the ground.

His friends who were still at the flat heard him and ran from the property and found him on the road.

Ms Brannagan said: “Mr McNab was bleeding from a wound to his stomach and was heard to say ‘help me, help me, I’m dying’.”

Ambulance crews arrived and found the victim had sustained four stab wounds – three to his left thigh and one to his abdomen.

The prosecutor said: “John McNab went into cardiac arrest. Advanced life support measures were carried out, with efforts continuing for some 40 minutes, unfortunately without success.”

Police who attended the scene heard comments indicating that the youth was responsible for the attack.

The prosecutor said: “They were clear that there had been an issue with the accused earlier in the night, but that John McNab had played no part in it.”

Officers later recovered a hunting knife with Mr McNab’s blood on the 20cm long blade and DNA from the teenage killer on the handle.

A post-mortem revealed that a wound to the victim’s abdomen had penetrated about 10cm deep and damaged the largest artery and vein in the body, resulting in fatal bleeding.

The murder came after the youth carried out the earlier attack at Portobello beach, where an event was organised through social media. During it, he made offensive remarks and was asked to stop by a teenager, before they got into a fight.

The teenager and his friends walked away, but the youth approached them and produced a hunting knife and threatened to stab the teenager. He pursued him and struck him on the back with a knife in a slashing motion.

The court heard that the killer was aged 16 when he carried out the knife attacks. The first offender was seen by a psychiatrist and was diagnosed as suffering from autism spectrum disorder and complex post-traumatic stress disorder.

The judge, Lord Harrower, deferred sentence on the youth for the preparation of a report until next month at the High Court in Dundee.

He said he will consider a motion by the BBC to lift reporting restrictions on the identification of the youth at that stage.