Once they would have tried to kill each other as rival gang members in Los Angeles. Now Louis Perez and David Andrade work together to raise awareness of the work of Homeboy Industries.

Last week the former gang members told their stories of how their lives had changed at an event in Glasgow hosted by the Scottish Violence Reduction Unit.

Perez, 35, is director of personal development at Homeboy and hopes to soon be working in the probation field. When he first walked through the door of the organisation around 10 years ago, his life as a gun-carrying member of a gang was very different.

Perez said memories of childhood included his father badly beating his mother when he was just four years old – which was the “end of innocence” – and a bullet coming through the wall and narrowly missing him as he played in a bedroom at home. His father left the family and his mother was an alcoholic – which led him to “run to the streets”.

He said: “No hopeful kid joins a gang. The reality is a kid that lacks hope is going to look for something that fulfils that hope. They run to the street because it is not happening at home.”

The first time Perez was sent to prison he was just 12 years old and he subsequently served lengthy sentences for violent crimes. But the fatal shooting of a close friend – who was planning to go to Homeboy in the hope of securing a job – by a rival gang prompted him to change his life.

“I saw was his body lying lifeless on the floor and his mother crying over her baby’s body,” he said. “Immediately retaliation was the first thing I thought about – but no matter how many times you retaliate, it never brings someone back. And that is when I thought about the last conversation we had about Homeboy Industries. So I walked there and asked to speak to Father Greg.”

He added: “It is about giving people the opportunity – sometimes we are crossed off before we are even given an opportunity or a chance.”

Andrade, 30, went to Homeboy after being released from prison in 2013. He now tutors others going through the 18-month job training programme.

Andrade said when he was young his mother was an alcoholic, his father was not around and he “idolised” a former gang member who had “the money, the fast cars and the beautiful women.”

He said: “I was 13 years old and seeing how he was living, I wanted to be like that.

“Being in a gang, being violent, doing drugs, selling drugs – I had no-one to tell me that was wrong. I just grew up where that was the norm.”

By the time he was 18 he had been arrested and was on a path as a “career criminal” who wanted to be the “baddest gangster”. But after a nine-year sentence in prison – including six years in solitary due to his “troublemaking” behaviour – he decided to change his life.

He said: “I saw the beatings, the stabbings, the riots going on – everything that happens in a prison yard.

“I made a promise to myself and that eventually if I was to make my release date – I want to work, I want to be with my family and I want a little joy in life.

“After all that time in prison, it finally clicked this isn’t the lifestyle I want.”

He said that when he and Perez were active in gangs, they would have been enemies who would “literally killed each other".

“Homeboy helped us change that outlook,” he said. “Your worst enemy becomes your best friend, like a brother.

“Without all the help, I would be dead or in prison.”