The head of Scotland's Violence Reduction Unit has challenged businesses in Scotland to give hundreds of staff a day off a month to mentor youngsters in danger of becoming criminals.

Detective Chief Superintendent John Carnochan, director of the VRU, has called for companies to invest in social responsibility by providing male role models to prevent young people entering the cycle of knife crime or becoming further embroiled in gang fighting.

Experts in mentoring hardened gang members from Chicago, Boston and England are coming to Edinburgh next month for a conference organised by the VRU that will explore crime deterrence through positive role models.

Mr Carnochan said: "I would like to see HBOS and the Royal Bank of Scotland and other businesses giving their employees one day off a month to mentor young people who are struggling either with their exams or because their parents are getting divorced or because they are on the cusp of getting into trouble.

"I want to see that big brother, big uncle notion right through the scale from those who need really intensive mentoring from groups like Includem and those who just need some guidance. It means they can also tick the social responsibility box.

"Why not involve Tesco, Morrisons and Asda?

"My idea of mentoring is done by ordinary individuals in the community who work and have good relationships with friends and family. It could be a bus driver, a train driver or a brickie, or someone who works in a bank.

"We are not saying single parents are bad, but when you're bringing up children on your own as a man or a woman it is more difficult. It is about helping to support people.

"There are already pockets of mentoring going on in different parts of the country, but it is about co-ordinating it. We are still at the early stages of looking at this."

Jo Hobbs, from Chance UK, an organisation that mentors five to 11-year-olds, will be speaking at the VRU conference next month.

The organisation has just established a project with NCH in Inverness, mentoring the children of alcohol and drug-addicted parents.

"We know from research that children displaying aggressive behaviour at this age are more likely to develop that behaviour as they get older. We use volunteers, whom we train.

"The employers recognise that allowing their staff to do this sees real benefits, including improvements in negotiation and communication skills. Eighty-five per cent of the children we work with are boys and the majority of them have no positive male role model in their lives.

"Some companies do allow their staff the time to do this but it is not as widespread as it should be."

The Scottish Mentoring Network has some 400 charities and companies on its database including Standard Life and Hewlett Packard, but schemes and their availability varies widely across the country. KPMG is also on their records for offering some employees half a day a month for time off to do mentoring or other community work.

Employees at HBOS currently get a day off a year to do volunteer work of their choice and can get contributions towards the charities they work with.

A spokesman for HBOS said: "It is hugely important for businesses to engage with community projects. We cannot go about our business without actively working with the community we're operating in.

"We have one of Scotland's leading staff volunteer schemes because we are one of the largest private sector employers in the country with a staff of 17,000. And 5500 employees volunteer annually out of our UK staff of 65,000. Some of them are involved in mentoring."

A number of companies are already involved. The Lloyds TSB foundation is helping to fund the project in Inverness.

Charities such as Apex Scotland, NCH and the Prince's Trust offer different mentoring programmes.