Three-time Grand Slam champion Andy Murray breaks down when broaching the subject of the 1996 Dunblane School massacre which is a topic he rarely addresses (AFP Photo)

London, United Kingdom — Former world tennis number one Andy Murray reveals for the first time in a new documentary that he suffered from breathing problems and anxiety following the Dunblane School massacre.

The 32-year-old and his older brother Jamie were pupils at the school in Scotland where on March 13, 1996, Thomas Hamilton shot dead 16 children, aged five and six, and a teacher in the gymnasium.

Andy Murray, then eight years old, had been on his way with his classmates to the gym when Hamilton — armed with four handguns and 700 rounds of ammunition — opened fire.

He was ushered away and told to hide under the windows of the headmaster’s office whilst Jamie, who is 15 months older, was in another classroom.

Murray has rarely spoken about the massacre and did not want to be filmed talking about it.

But the documentary ‘Andy Murray: Resurfacing’ includes a voice-note that the three-time Grand Slam champion and two-time Olympic gold medalist sent to filmmaker Olivia Cappuccini.

“You asked me a while ago why tennis was important to me,” says Murray in the documentary due to be released on Amazon on Friday.

“Obviously I had the thing that happened at Dunblane. I am sure for all the kids there it would be difficult for different reasons.

“The fact that we knew the guy (Hamilton), we went to his kids’ club, he had been in our car, we had driven and dropped him off at train stations and things.”

Murray, who bursts into tears halfway through the voice-note, says the massacre precipitated a further traumatic sequence of events in the family.

“Within 12 months of that happening, our parents got divorced,” he said.

“It was a difficult time that, for kids, to see that and not quite understand what is going on.

“And then six to 12 months after that, my brother (Jamie) moved away from home.

“He went away to train, to play tennis. We obviously used to do everything together. When he moved away that was also quite hard for me.”

Murray admits that is when he suffered from anxiety but tennis has provided an escape for him.

“Around that time and after that, for a year or so, I had lots of anxiety but that came out when I was playing tennis,” said Murray.

“When I was competing I would get really bad breathing problems.

“My feeling towards tennis is that it’s an escape for me in some ways, because all of these things are stuff that I have bottled up.

“We don’t talk about these things. They are not things that are discussed.”

“The way that I am, on the tennis court, I show some positive things about my personality and I also show the bad things and things I really hate.

“Tennis allows me to be that child, that has all of these questions.

The documentary follows the two-time Wimbledon champion as he attempts to recover from a hip injury that threatened to end his career.

Following surgery earlier in the year, he has rejoined the ATP singles circuit.

He won the European Open in Antwerp in October, his first title since 2017, and helped Great Britain reach the semi-finals of last week’s Davis Cup in Madrid.