A previously law abiding citizen "snapped" and stabbed at a rival 15 to 20 times in a frenzied attack, a court heard.

Schools were put on lockdown after parents picking up their children witnessed the terrifying scene in Dartford.

Razak Osomo had never committed a crime until late September when he armed himself with a hunting knife and a lock knife and went in search of Joshua Olbrechts.

The 23-year-old McDonald’s worker had reached breaking point after a number of incidents involving the victim around the Willow Road area of Dartford, Woolwich Crown Court heard.

Charles Langley, defending, claimed Mr Olbrechts had subjected the Osomo family to a campaign of bullying and harassment.

In 2014 Mr Olbrechts, 25, was arrested on suspicion of assaulting Osomo’s father, but never convicted.

Video footage of another incident shows him standing outside the Osomo family home and hurling abuse, he said.

“It was absolutely terrifying for those who saw him for obvious reasons in the current climate." — Ian Hope, prosecuting

Mr Langley added Osomo, who was initially charged with attempted murder, did not use these incidents as an excuse for his actions.

At around 3pm that day, members of the public in Sycamore Road, Dartford – many of whom were on the school run – saw Osomo dressed in camouflage and wearing a balaclava, backpack and motorbike gloves running past schools holding a large knife.

Ian Hope, prosecuting, said: “It was absolutely terrifying for those who saw him for obvious reasons in the current climate. Schools in the area – Dartford Science and Technology College, Wilmington Academy and Westgate Primary School – were put on lockdown.”

Mr Olbrechts, his friend Lewis Back and other associates were standing by cars in Heath Lane when Osomo – previously of Willow Road, Dartford – appeared.

Mr Hope said: “He was carrying out a planned attack on Joshua Olbrechts. When Osomo arrived he repeatedly asked: ‘Are you done?’ Despite wearing the mask the group recognised his voice.”

Osomo gestured with the knife towards Mr Back who fled to his vehicle. He then began stabbing at Mr Olbrechts in what was described by a witness as a frenzied attack.

Mr Back told police he saw Osomo make 15 to 20 attempts to stab Mr Olbrechts, who eventually managed to shut his car door. He sustained three cuts to his right arm, one of which needed stitches.

Osomo fled on foot along Heath Lane and into a garden where he was cornered by police. When they threatened him with a Taser he surrendered and told them where the knives were.

Jailing him for nine and a half years after he admitted wounding with intent, Judge Nicholas Heathcote Williams QC said: “You have a perception that you and your family had been bullied and harassed, although there is no evidence of provocation. You in fairness acknowledge this does not excuse your actions.”

Osomo, who also previously admitted possession of a knife and using it to threaten Mr Back, was also sentenced to two and a half years for each charge, to run concurrently. An attempted murder charge will lie on file. He will be eligible for release after four years and nine months.

In a letter to the judge read out by Mr Langley, Osomo expressed his remorse for his crimes.

He wrote: “I’m writing this in all hope you may get a better picture of my character. I was a law-abiding citizen. I was going to be promoted to management and make my family proud. I am disgusted at my actions and view them with regret and shame.

“I am apologetic towards the victims, their family, those who witnessed the incident and you for having to deal with my case.”

Mr Langley added that Osomo had not been in trouble before, had never been in a gang, which was “not easy” given the area he lived in, and had moved to Deptford away from Mr Olbrechts.

He had behaved impeccably in prison, determined to use it as a positive experience.

Investigating officer Detective Constable Lucy Macland said: "This was a particularly vicious and targeted attack on two men who were known to Osomo.

"Osomo was clearly intent on inflicting as much damage as possible. He lashed out at both men in a frenzied manner and it’s very fortunate that only minor injuries were suffered.

"He was stopped and arrested shortly after the attack. I’d like to thank the public for their vigilance in reporting the incident immediately and providing a good description that aided us in detaining Osomo."