A woman police officer posed as a young girl on the internet to trap a pervert looking for under-age sex, a court heard.

The officer stepped in when a 15-year-old girl complained Martyn Palmer had tried to groom her on the social networking site Facebook.

Maidstone Crown Court heard the 38-year-old, of Butchers Lane, Mereworth, sent the detective photos of him exposing himself and performing a sex act on a webcam.

Palmer was jailed for 18 months after admitting arranging to meet a child following sexual grooming.

Anne Phillips, prosecuting, said Palmer was fully aware of the girl’s age after making contact with her but made it clear he wanted to meet her and have a sexual relationship.

The officer took over the victim’s internet account and contacted Palmer. The conversation became increasingly sexual, said Miss Phillips.

When arrested in September last year, he denied having a sexual interest in children and claimed the girl told him she was 16.

Judge Charles Macdonald QC said he rejected a submission Palmer was deeply remorseful.

He was placed on the sex offenders’ register for 10 years and will be subject to a sexual offences prevention order for 15 years.

Investigating officer DC Mike Brown said: "Palmer actively sought out children on the internet in order to pursue his sexual interests. I would commend the actions of the original victim in notifying police, allowing this investigation to take place.

"Any person who is concerned about an approach made to them on the internet should report the matter either to CEOP through their online reporting system, or to their local police."

After the sentencing, police urged parents to be aware of the dangers of children using the internet and said that safety advice is available at www.kent.police.uk

Anyone who has information on this type of crime can ring Kent Crimestoppers anonymously on 0800 555 111 and anyone who is involved in this type of crime and wants to stop can visit the website www.stopitnow.org