A ‘young and academically gifted’ teenager has been imprisoned in a ‘very sad and tragic case of affairs’, a court has heard.

Frazer Denboer had just achieved A and B grades in his GCSE exams before he robbed two Grove stores earlier this year, threatening to kill the cashiers if they did not open the tills.

The 18-year-old, who had been using drugs since the age of 13, was using a sprayed BB gun during the robberies and made off with £90 and £370 to pay off drug debts.

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Sentencing him to three years in a young offenders institute at Oxford Crown Court on Monday (September 30), Judge Maria Lamb described the case as ‘tragic’.

“It’s very sad for your family,” she said. “And I’m very sad for you too, brought to this by drugs. It’s not an exaggeration to say this is a very sad and tragic case of affairs but one has to be sad for those unfortunate victims.”

The court heard that on April 15, Denboer approached the till in a Tesco store in Millbrook Square at 6.30am in the morning, holding a bottle of wine with his hood over his head.

He told the cashier to open the till and give him all the money or he’ll shoot her, whilst pointing the BB gun towards her.

The cashier called over her supervisor who told Denboer she could not open the till or she ‘would lose her job. The teen said if she did not do what he said, she ‘might lose her life’.

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He was handed £90 and made off from the store. A week later, on April 28, he walked into the Bottle Top store in Millbrook Square at 6pm wearing a balaclava.

The teen told the cashier he’ll ‘have all the money from the till’ whilst similarly holding the gun towards him. He was handed £370.

None of the victims believed the gun was real but the first staff member described the incident as ‘terrifying’ and said she has been ‘traumatised’ by what happened.

Her supervisor similarly said she now suffers panic attacks due to the robbery and has had ‘sleepless nights involving shaking and sweating’.

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Defending Denboer, of Vale Avenue, Grove, barrister George Joseph described his client as ‘very young and academically gifted’.

Describing the teen’s drug addiction, Mr Joseph said: “He suffered an overdose a number of years ago which has caused some brain damage…it’s a tragedy that his mind has gone to waste.”

Denboer has no previous convictions and was supported by family members in court.