A train passenger who stabbed an IT consultant 18 times after a row over aisle blocking has been found guilty of murder.

Jobless Darren Pencille, 36, launched an "unrelenting" and "savage" attack on 51-year-old Lee Pomeroy following a heated argument in front of the victim's 14-year-old son.

Other travellers on the Guildford to London service in January were horrified when Pencille produced a knife and repeatedly stabbed the unarmed man.

The defendant, who declined to give evidence at his Old Bailey trial, had admitted having a knife but denied murder, claiming he had acted in self defence against the 6ft 3in tall victim.

But jurors heard how 5ft 10in tall Pencille had a history of violence, having previously stabbed a flatmate in the neck over a minor disagreement in 2010 and had threatened to kill a staff member at a mental health hostel in June last year.

A jury deliberated for 19 and a half hours to find Pencille, of no fixed abode, guilty of murder.

His girlfriend, Chelsea Mitchell, 28, of Farnham, was found guilty by a majority of 11-1 of helping him evade police after the attack.

Following his conviction, British Transport Police Detective Chief Inspector Sam Blackburn described Pencille as "devious and dangerous".

He said: "He's a dangerous man. Quite clearly with his previous convictions, where he also stabbed another man in the neck, and his propensity for carrying knives, he showed his dangerous, aggressive nature and that he wasn't afraid to use that knife on that train on January 4."

Mr Pomeroy had boarded the train at London Road, Guildford, on Friday January 4 for a day out in London with his teenage son, ahead of his 52nd birthday.

Father and son had got into the same carriage as Pencille and made their way down the aisle, the court heard.

Jurors heard they may have been "blocking" Pencille's way, prompting the snide response: "Ignorance is bliss."

A heated argument erupted, with Pencille swearing at Mr Pomeroy and calling him a "pussy".

Pencille shouted: "You touch me, you touch me and you see what happens at the next stop."

Mr Pomeroy was said to have demanded an apology, saying: "You should not have humiliated me in front of my kid."

At one point, Pencille was heard to say on his mobile phone: "I'm going to kill this man", the court heard.

As Mr Pomeroy remonstrated, Pencille swung the knife and plunged it into his neck, cutting through the jugular vein.

Prosecutor Jake Hallam QC had told jurors: "Eyewitnesses saw what they thought was the two men trading punches. They were half right.

"They saw Lee Pomeroy punching the first defendant, defending himself, having been stabbed in the neck by him.

"But the first defendant wasn't punching back, he was stabbing. Again, and again, and again."

Pencille got off at the next station, leaving Mr Pomeroy mortally injured with 18 knife wounds to his neck, torso, thigh and arm.

Mitchell picked up the defendant and bought hair clippers and razors for him to change his appearance, jurors heard.

Jurors were told paranoid schizophrenic Pencille had been seen by psychiatrists since 2004 but had not taken any anti-psychotic medication at the time of the attack.

His mother Ingrid Robertson told jurors: "He always thought people were looking at him or wanted to do something to him."

Following the earlier incidents of violence, the defendant had pleaded guilty in February 2010 to causing grievous bodily harm and common assault in June 2018.

Last month, while Pencille was in jail awaiting his trial, Mitchell sent him a Father's Day card in the name of their stillborn son, in breach of her bail conditions.

In the note, she told him: "I miss you so much, everything is falling apart. Loosing everyone I love and all I want us my family back (sic)."