Scotland's Children's Comissioner has backed a campaign to ban a device that deters youths from loitering by producing a high-pitched sound only the young can hear.

The appliance, called the Mosquito, uses young people’s ability to hear high frequency noises, an ability which diminishes when people reach their mid-20s.

As many as 3,500 Mosquitoes are estimated to be in operation across the UK to disperse children and teenagers in public areas such as parks and shopping centres.

Kathleen Marshall, Commissioner for Children and Young People, joined civil liberties campaigners in condemning the device and agreed that it did not respect children's rights.

Ms Marshall said: “The ‘teen tormentor’ or ‘teen repellent' is an ultrasonic weapon used against our children and young people indiscriminately. Its use would not be tolerated for any other section of our society. Young people have a right to assemble and socialise with their friends, without being treated as criminals.

“There needs to be an outright ban on this device which affects not only teenagers, but also young children, babies and young people with disabilities.”

The "Buzz Off" campaign was launched in England two weeks ago by Professor Sir Al Aynsley-Green.

In December, Ms Marshall described the devices as "sinister" and called for them to be withdrawn from sale. In a statement on 12 February, she vowed to continue to lobby the Scottish Government, the police, supermarkets and the device's manufacturers for a ban.

The exact number of Mosquitoes in use in Edinburgh is unknown.

A spokesperson from Compound Security Systems, the manufacturers, said that because the devices are available online, it is hard to be sure how many are being used in any one area.

John Loughton, chair of the Scottish Youth Parliament, said: “If ever there was a device which highlighted the terrible way in which young people are treated in society then this is it. Since when did standing in an area become a crime?”

The Mosquito was invented by Howard Stapleton, from Merthyr Tydfil, South Wales. Mr Stapleton stated that a test case in the courts might be the only way of establishing the legality of the device.

Shop owner Rob Gough from Barry in South Wales, who was the first to test out the device, said he would defy any ban.

Mr Gough, who has used the Mosquito for over two years, said “It's been a great success for me.”