Teen hackers tell BBC how police are helping them use their skills for good

Lucas said he felt a "sense of achievement" from hacking

Lucas was 16 when he got into trouble for hacking his school computers. Twice.

"It was like a challenge to see if I could," he told the BBC.

He wanted access to play games and visit blocked websites so he started tinkering with programming.

At one point he even unscrewed the computer tower to take some internal components home for tests.

"It's quite a sense of achievement when you've succeeded in doing something that two or three trained professionals have spent a lot of time trying to stop you doing," he said.

He was close to being expelled - but his worried mother had no idea how serious his actions were.

She called the police and invited an officer from the nationwide programme Cyber Choices to their home in rural Cumbria.

"My mum was like, 'ooh, you've got a detective coming to speak to you, you're in a lot of trouble'," Lucas said.

"So I was sat at the window waiting. Who's going to come? How much trouble am I going to be in?"

PC Sam Cooper, a cyber prevent officer, knocked on the door earlier this year and he has been working with Lucas ever since.

PC Sam Cooper visits children at their homes to guide them away from cyber criminality

He explained to Lucas, as he has with dozens of other children, there are real consequences and harm caused by cyber-attacks.

Cooper said showing the mostly teenage boys what was legal and not was step one.

Then comes positive encouragement over months of one-to-one meetings, usually at their homes.

"I'll try and find where their interests are and try and divert them towards professional training, qualifications," he said.

Cyber Choices, also known as Cyber Prevent, is like a hacker rehab course.

It works in parallel with the more well-known Prevent scheme, which identifies potential terror offenders.

While at Lucas's house I saw first hand how some of the conversations work.

Lucas enthusiastically explained his latest computer experiments and Cooper asked him what software and tools he was using to check they were legitimate.