A husband who heard his wife being stabbed to death by a schizophrenic on the other end of a phone line had viewers in tears as he was forced off SAS: Who Dares Wins through injury.

Danny Cross's wife Nicola was killed as she tried to protect her children when a man broke into their Hertfordshire home in 2015. Her husband was on to phone to her and heard the horrific attack unfold.

The 40-year-old appeared on the latest series of Channel 4's SAS: Who Dares Wins, in which ex-Special Forces soldiers put recruits through a gruelling recreation of the SAS selection process.

As he was forced off of the show by a knee injury last night, he paid tribute to his children for getting him through the family's tragedy.

Danny Cross, whose wife was stabbed to death as he listened on the other end of a phone line, spoke of the tragedy as he appeared on Channel 4's SAS: Who Dares Wins last night

Mr Cross lost his wife Nicola (pictured together) when she was brutally stabbed to death at their home in Hemel Hempstead in 2015

Reliving the night of his wife's death, he said: 'It was late one night. I was working away from home and my wife called me to say she was worried about a man that had been hanging around outside the house.

'She was on the phone to me when the man broke in through the back door. A schizophrenic. He had a knife and he picked up another knife from the knife block and killed her.

'I was on the phone to Nikki and heard everything. I heard children crying at the other end of the phone. I could Isabella trying to wake mummy up. saying "wake up, wake up".

'A few minutes later I heard the police arriving and I had to cut the line then. I couldn't listen to anymore.'

His determination to keep going after the incident led him to go on the show, which tests entrants to their limits.

He told the show's instructors: 'I could have crumbled in that situation. I just had to keep going for the kids. I think that without them I would be in a very different place, I'm sure of it.

'Even though they miss mummy, they are happy kids.

'It gives you an inner power to know that you can cope and you can deal with things. Not a lot fazes me now.'

Instructors of the show shook his hand after he told them what he had been through

The 40-year-old was forced off of the show after developing a serious knee injury

Mrs Cross was described as 'the perfect wife and most amazing mummy' after death. Her family have since set up a Facebook group called Nikki's Wishes in her memory

Viewers were left in tears by his bravery and determination to keep going.

Nathan Sweett tweeted: 'The amount of admiration I have for this man holds no bounds. To be able to carry on after such an ordeal is truly amazing. Danny Cross, you are a true hero.'

BP Baker added: 'In my eyes Danny Cross is the winner! Regardless of being withdrawn, nothing will ever break that man. Well done for being strong for your family!!'

Kirsty Purnell added: 'I think he deserves everything what an amazing bloke I was crying just can't believe what nasty people are in this world it's terrible. But Danny be proud for your family we all believe in you xx'

Mr Cross wrote online earlier this week: 'Some really nice feedback received in relation to the SAS Who Dares Wins TV show.

'It's reaching people like this that was one of the key reasons I decided to take part in the show. I hope the show & my experience continues to connect with people.'

His bravery on the show won praise from viewers, who said he was the real winner

Mr Cross, an IT specialist, was 200 miles away in Hull when, during a phone call with 37-year-old Nikki, he heard her desperate fight for life.

In a statement released after her death, her family described Mrs Cross as 'the perfect wife and most amazing mummy', and somebody who taught those around her never to give up.

The statement said: 'Our Nikki is the heart and soul of our family. She was kind, generous, brave and incredibly talented.

'The most beautiful person inside and out, Nikki was the perfect wife and the most amazing mummy.

'She installed core belief in our children to never give up and we will continue what she has built, which is a solid loving family who will remember her with undying love'.

Polish warehouse worker Marcin Porczynski is currently detained in a secure psychiatric unit for the murder of Nicola Cross

Marcin Porczynski, then 27 and a schizophrenic, broke into her home late at night on 14 September 2015 intending to kidnap her two young children.

Porczynski later pleaded guilty at St Albans Crown Court to Nikki's manslaughter on the grounds of diminished responsibility and was ordered to be detained in a secure psychiatric unit for an indefinite period.

Mr Cross told the court that the phone call 'plays over and over in my head'.

In a statement to the judge, he added: 'I will never forgive myself for not being there to protect her.'

Since the attack, Mr Cross, who lives in Hemel Hempstead with his two children, has been trying to rebuild his life.

Last year, he posted on the Facebook page the news that he was training to be a volunteer counsellor with the Homicide Victim Support Service so that he could help other families going through the nightmare of losing someone in violent circumstances.

Writing at the time, he said: 'For me it is essential that I use what happened to my family in a positive way to help other families going through the toughest of times. If I can help them to get to the same point I am now, then I will be happy.'