MARINE A has spoken about about the killing which saw him become the first British soldier to be convicted of murder on the battlefield.

Alexander Blackman, who is Brighton born and raised, spoke exclusively to the Daily Mail in a wide-ranging interview in which he also discussed what it was like to be home.

The 42-year-old was released from jail last month after his murder conviction was quashed in the Appeal Court court.

He was jailed in 2013 after head camera footage showed him shooting an injured insurgent Afghanistan.

Speaking to the Daily Mail about the killing, he said: “I know I made a terrible mistake.

“I don’t know why I did it. I think about it a lot and have done ever since but I still can’t put an exact thought to why I did what I did at that moment in time. I wish I could.

“It was frustration more than anything.

“There had already been a reasonably large attack on a friendly base.”

His wife Claire, who led the campaign for his release, said: “It was a theatre of war. He was the enemy. There are so many facets you can’t possibly take into account from the comfort of your sofa watching five minutes’ worth of video clips from an incident that lasted an hour.

“It is not right or fair to judge what happened in those few minutes without understanding absolutely what it means to be out on the ground.”

The pair also spoke about what it was like to be back together after four years apart.

Claire said: “I can’t believe how quickly we’ve gone back to being the couple we were before.

“You could almost wipe the last four years from your memory and pretend they didn’t happen. I knew how solid our relationship was, but it’s so lovely we have absolutely picked up where we left off.

“Maybe I never took the time to understand what marriage vows genuinely meant before Al’s arrest. I never really thought them through. I think I know now. I never doubted Al. You can see how calm and kind he is. But I could tell that tour was different.”

Talking about his time behind bars, he said: “It’s the conversations you can only have as a couple that you miss.

“I tried to speak to Claire every day. Any work I did in prison was solely about earning money for the phone to talk to her. Now we can have conversations spontaneously, not just in a 20-minute phone call in the evening.”