THE inventor of a device criticised as an "ultrasonic weapon" has attacked a company using it and called it "stupid" for deploying it at a railway station.

Howard Stapleton, who created the "mosquito" device which emits a high-pitched sound which causes discomfort to children, said First Great Western had been wrong to use the device constantly at Teignmouth station in South Devon.

The rail operator said it will not activate the device when passengers are travelling, after complaints from children getting to school by train.

But the company said it would continue to use it late at night, when the station was most at risk from vandalism.

But Mr Stapleton defended the machine, saying it was wrong to call it a "weapon", after local MPs called for it to be banned.

He said: "I am aware of this incident where they had the device running constantly. That is absolutely stupid.

"Nobody should use the device 24/7. It is completely safe but could be used incorrectly.

"As the inventor and owner of the company I would be really pleased to work with MPs and police about its fair and proper use.

"I would be very pleased to have a meeting with the MPs in question and also to see legislation to govern the fair and appropriate use of the device."

Since its installation, First Great Western says there had been a big reduction in graffiti and crime at the station.

The device emits a high-frequency sound which is normally audible to people under the age of 25, to disperse groups of youths.

A Parliamentary petition has now been tabled by Teignbridge's Lib Dem MP Richard Younger-Ross, highlighting the growing use of the devices.

It also agrees with the Children's Commissioner Sir Alan Aynsley-Green that these are "ultrasonic weapons designed to stop young people gathering, which are a powerful symbol of a deep malaise in British society and its views towards children".

The Commons motion, which already has the backing of nearly 20 MPs including Adrian Sanders for Torbay, also states "that their use in public places where children legitimately gather is wrong" and calls on the Government "to urgently limit their use".

Mr Younger-Ross last week raised the issue at Westminster with Commons Leader Harriet Harman.

He said: "Such devices are used on railway stations during the rush hour when young people are going to school or college, and outside shops where young mums, who cannot hear them, leave their children, who can hear them, in distress, so may we have, as a matter of urgency, a debate on the rights and protection of young people?"

Ms Harman felt it was an issue that would interest a number of MPs and Mr Younger-Ross should look to secure a debate.