TENNIS pro Andy Murray was just eight years old when Thomas Hamilton walked into his school gym and opened fire on a class, killing 16 children and their teacher.

His class was on their way to the gym when the sound of gunfire rang out. Murray took refuge under a desk in the headmaster’s office.

The Dunblane Primary School massacre on March 13, 1996, changed Britain forever, ushering in the introduction of the strictest gun laws in the world.

Now exactly 20 years later, in memory of those who lost their lives, and the town that rebuilt itself after the tragedy, Murray has posted an emotional tribute to his Instagram.

“Always in my thoughts. Take you with me everywhere I go. Always my home,” he wrote, alongside the picture.

Murray and his family have previously revealed the heartache they felt after the massacre, and how close he and his brother Jamie came to losing their lives.

In his 2008 autobiography Hitting Back, Murray said he often thought about how he could have been one of the children who lost their lives.

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“Some of my friends’ brothers and sisters were killed. I have only retained patch impressions of that day, such as being in a classroom singing songs,” he wrote.

Murray and his family also knew the gunman personally, previously giving him lifts in their car and attending a youth group run by Hamilton.

“The weirdest thing was that we knew the guy. He had been in my mum’s car. It’s obviously weird to think you had a murderer in your car, sitting next to your mum,” he wrote in the book.

“That is probably another reason why I don’t want to look back at it. It is just so uncomfortable to think that it was someone we knew from the Boys Club. We used to go to the club and have fun. Then to find out he’s a murderer was something my brain couldn’t cope with.”

Murray’s mother Judy said she was left panicked after she heard what had happened at the school.

“I was one of hundreds of mums that were queuing up at the school gates waiting to find out what had happened, not knowing if your children were alive or not,” she said.

His brother Jamie, who was also a student at the school when the massacre occurred, said he was glad the town could be shown in a positive light now.

“I guess that’s a testament to the success that Andy’s had,” he said on BBC’s documentary Andy Murray: The Man Behind The Racquet.