An epileptic boy whose cannabis oil was seized by the Home Office is in a life threatening condition after suffering seizures.

Billy Caldwell, 12, was rushed to Chelsea and Westminster Hospital in London after his epilepsy seizures 'intensified', a family statement said.

A batch of the banned drug used to treat him was confiscated from his mother Charlotte Caldwell at Heathrow Airport, and she said the Home Office would be held accountable if he died.

Billy was deemed too sick to be treated at home with 'rescue meds', which means only hospital-administed medication can be used if he has another seizure, a family statement added.

Charlotte and Billy Caldwell in happier times. The 12-year-old was rushed to hospital after suffering a seizure

The statement continued: 'While Billy has recovered from back-to-back seizured it now means limited options for ongoing treatment, with doctors in Canada and Northern Ireland family with Billy's case now saying the situation is life-threatening.

'He is now too ill to travel back to Canada for treatment meaning the only effective medication is locked in secure storage in the Home Office in London.'

They added that doctors were 'horrified' Billy was being deprived of the medication.

Ms Caldwell said: 'This is beyond cruelty. We've now reached the point where Billy is too ill to travel to get his medication, but his medication is stored minutes away from where we're now living in London.

'Despite the best and honest efforts of the NHS, frontline doctors are fighting Billy's condition with both hands tied behind their back because the only medication that will be effective is the cannabis oil (with a banned component).'

The child, from Castlederg in Co Tyrone, started the treatment in 2016 in the US, where medical marijuana is legal.

He became the first person in the UK to receive a prescription after his local GP in Northern Ireland, Brendan O'Hare, began writing scripts.

However, there is no record of a health service prescription being dispensed.

Billy Caldwell with his mother Charlotte. She had said if her son were to die, the Home Office would be held responsible

Dr O'Hare was summoned to a meeting with Home Office officials recently and told to desist.

Ms Caldwell made the journey to Toronto, Canada with her son to get a six-month-supply to treat up to 100 seizures a day - but border officials seized the oil.

She added: 'Billy has had back-to-back seizures today, Friday.

'On his medication, which included the vital but banned THC component, he was seizure-free for more than 300 days.'

'If Billy dies, which is looking increasingly possible, then the Home Office, and (minister) Nick Hurd, will be held completely accountable.'