PRONOUNCED ᎠᎬᎪᎠ — BUT HE WAS ALIVE Police told parents their teenage son had diҽd in a crash… They mourned him for THREE WEEKS — before learning he was actually alive in hospital.

A mix-up which saw police wrongly tell one family their son had died in a car crash and another that theirs was badly injured left relatives grieving a teenager for three weeks – when he was alive in hospital the whole time.

The staggering blunder meant the family of one boy, 18-year-old Joshua Johnson, spent Christmas believing he was under sedation in hospital – only to be told he in fact passed away in the tragic smash.

Meanwhile, another family discovered the son they have been grieving for the past three weeks, 17-year-old Trevor Wynn, is in fact still alive.

The unthinkable mistake emerged when the teen regained consciousness on Sunday and told shocked medical staff: ‘I’m Trevor.’

Joshua’s parents were then given the heartbreaking news of the terrible error, saying of Trevor: ‘That’s not our son.’

Sources said the serious injuries the surviving boy sustained meant no one spotted he wasn’t Joshua until he woke up. Additionally, Joshua and Trevor – known as TJ – are said to be similar in appearance.

On Tuesday it was confirmed that, after new forensic tests, the body was wrongly identified after the crash and was in fact Joshua’s.

Trevor’s family have been preparing for his funeral later this week, it is understood, but are now coming to terms with the astonishing news he is still alive.

The police watchdog is investigating the unthinkable mistake made by officers following the collision near Rotherham on December 13.

In a grovelling apology, a police chief said he had offered to meet both sets of parents to try to give them an explanation – and pledged to make sure such an unforgivable error ‘cannot happen again’.

Police originally said Trevor Wynn, 17, pictured, was killed when the Toyota in which he was a passenger left the road and struck a tree on December 13 – but today revealed he survived and is in hospital, and the boy who died was in fact 18-year-old Joshua Johnson

The vehicle left the carriageway between Dinnington and Todwick, near Rotherham, South Yorkshire, pictured

After the crash, South Yorkshire Police announced that Trevor had been pronounced dead at the scene.

A second teenager, a 17-year-old girl, also tragically died when the Toyota in which they were travelling left the road and struck a tree, while a third teen was taken to hospital.

The force today revealed that on Sunday, ‘concerns were raised’ about the identities of the victims of the crash.

A new formal identification process took place, including forensics, which established that Trevor was in fact in hospital receiving treatment.

It meant the family of Joshua – who had been told he was under sedation in hospital being treated for his injuries – had to be informed that he was actually the boy who died.

Meanwhile, Trevor’s family were told he is actually still alive and has been in hospital since the collision.

Today South Yorkshire’s Assistant Chief Constable Colin McFarlane said: ‘This has obviously come as a huge shock to everyone and we recognise the additional trauma this may cause.

‘We are supporting Trevor and all the families through this and have engaged specialist agencies to help provide that support.

‘I have also offered to meet with both sets of parents as I am sure they will have many questions, most of which we are not able to answer yet but we are absolutely committed to understanding how this happened so it cannot happen again.

South Yorkshire Police Assistant Chief Constable Colin McFarlane said the force had referred itself to the Independent Office for Police Conduct (IOPC) since identifying the error

‘We have taken the decision to refer ourselves to the Independent Office for Police Conduct (IOPC) to consider our role in the identification processes which were followed following the road traffic collision.

‘We will co-operate fully with any subsequent investigation and will be led by the IOPC on the next steps to determine how this happened, and how we can ensure this never happens again in the future.’

At the time, police said their vehicle left the carriageway between Dinnington and Todwick.

Following the double tragedy, friends of Trevor – known as TJ – launched an online fundraiser to help his grieving family pay for his funeral.

On the page, the organiser wrote: ‘TJ was the most caring lad with a soft soul.

‘He always put others first and loved nothing more than making people smile.

‘Anyone who knew TJ knew how kind and genuine he truly was.’

At the time, Sergeant John Taylor from the force’s serious collisions unit said: ‘This is a tragic collision in which two young people have lost their lives with a further person in a critical condition, and we are committed to finding answers for their families.

‘Our enquiries are continuing, and we are keen to speak to anyone who may have footage of the car prior to the collision.’

The families and surviving victim will be offered support from specialist officers and additional specialist services, the force said today.

An 18-year-old was arrested on suspicion of causing death by dangerous driving, and a 19-year-old was arrested on suspicion of perverting the course of justice.

Both remain on bail pending further enquiries.