The 'Mosquito' sonic deterrent device was installed by the Wyvern Theatre in an attempt to stop groups of up to 100 youngsters from gathering around Theatre Square.

Click below to listen to a feature about the 'Mosquito' device from BBC Radio Swindon's Breakfast Show with Peter Heaton-Jones broadcast on 14/06/06. Help playing audio/video

The Wyvern Theatre It was named the 'Mosquito' because the sound resembles that of a buzzing insect. And it works by emitting a harmless ultra sonic tone that generally can only be heard by people aged 25 and under. In trials, it has proven that the longer someone is exposed to the sound, the more annoying it becomes.

Crime Reduction Officer Bob Walton elaborated further: "Effectively, it's a transmitter which sends out a specialised frequency noise which according to the manufacture is particularly audible to young people under the age of 25.

He said: "I'm in my fifties and when it's turned on all I can hear is a very faint buzz. But I understand from young people who have been exposed to the noise, it is very annoying."

Swindon's anti-social behaviour co-ordinator Cheri Wright says it is working well.

She said: "We had a meeting with local retailers arounds here - after it had been installed for around three weeks - and feedback was really positive.

"Everyone was saying there has been a marked reduction in criminal damage and problems with the shops, so they've really welcomed it."