A steward at the Britannia Royal Naval College in Dartmouth has been jailed after being trapped by two groups of internet vigilantes as he tried to contact 10 underage girls.

Michael Watton believed he was speaking to girls as young as 10 when he suggested having sex with them and was trapped after arranging to meet a 14-year-old for sex.

He was caught in sting operations run by two groups called Dark Justice and Internet Interceptors which had invented internet profiles for fictitious young girls.

Watton, 56, of Church Road, Dartmouth, first encountered the girls when they responded to his posts on adult dating websites but he quickly turned the conversation to sex, even though they told him they were underage.

He arranged meetings with two girls he thought were 14. He failed to turn up for the first but was intercepted by a vigilante group at Paignton railway station when he arrived for the second.

He later admitted he intended to take the girl, who he thought was called Ellie-May, to the cinema and a Chinese meal before going with her to a bed and breakfast for sex.

Some of Watton’s most explicit conversations had been with a decoy called Jess, who claimed to be just 10 years old, Exeter Crown Court was told.

He was trapped separately by the two groups and in total sent messages to ten decoy girls who used named including Polly, Kim, Katie, Sophie, and Tiffany.

Watton worked as a steward at the Britannia Royal Naval College before his arrest in October. The college trains all the Royal Navy’s officer recruits and Princes Charles and Andrew are former cadets.

Watton admitted attempting to meet a child after grooming and two counts of attempted sexual communication with a girl under 16. He asked for seven more to be considered.

He was jailed for 16 months by Judge Erik Salomonsen, who ordered him to sign on the sex offenders register and made a Sexual Harm Prevention Order which restricts contact with children and allows the police to monitor his internet use.

He told him: "Against the assertion that you were effectively a dupe is the fact that you went so far as to propose two meetings and attend one of them at Paignton station.

"The defence argue this sentence should be suspended because of your loneliness and vulnerability, but there must be immediate custody because of your willingness to embark on these exchanges with not one but ten individuals."

Julia Cox, prosecuting, said Watton’s contact with the decoy girls started in October last year and carried on for two weeks, during which he exchanged messages with what he thought were girls aged 10 to 14.

He posed half naked in his own profile and began contact with the decoys by asking ’are you single, luv?’.

He arranged to meet a 14-year-old called Katie in Newcastle, but never turned up. He told a girl called Jess, who he thought was 10, that he wanted to ejaculate inside her.

Watton organised a meeting at Paignton on October 21 with a 14-year-old decoy named Ellie May but was intercepted by members of the two groups as well as men from Plymouth based UK Database and Plymouth Against Paedophiles.

Mary McCarthy, defending, said Watton was living with his mother and was lonely after the death of his partner in a car accident.

He had gone online looking for adult dating and been lured and flattered into communicating with the decoys when they had replied to his profile.

She said: "The reality is that when you look at his profile picture, without wanting to be rude to him, in reality no young child is likely to have wanted to engage with him.

"He did not pose as an attractive young person. He was not pretending to be someone he wasn’t. He is a bearded man in his 50s who found to his astonishment that a number of young girls apparently wanted to engage with him.

"In the real world, it is not very likely matters would have progressed as they did. The groups could be said to lead people down a path they would otherwise not have gone on."