A festival worker was found with indecent images of children on his phone after he offered drugs to a plain clothed security guard.

Adam Bell, 19, was working on a food stall at the In It Together Festival in Margam, Neath Port Talbot, in May, when he offered ketamine to an officer.

Swansea Crown Court heard bags of the class B drug were found in his tent in the staff section of the festival at Margam Park, and police later found the indecent images after seizing his phone.

Bell, of Richmond, London, was jailed for two years and three months on Friday.

Police found 146 category A images – the most serious – of child abuse and some material had been shared with other people using the Telegram app.

The court heard Bell had shared a category A sex abuse video of a child aged between five and seven.

Bell’s phone also contained an “upskirting” video of a young female.

He pleaded guilty to making indecent photos of children, distributing indecent photos of children, voyeurism and possessing class B drugs with intent to supply.

Dean Pulling, prosecuting, said messages were found on Bell’s phone that described his “obsession” with child pornography.

Gerry Mohabir, defending, said Bell pleaded guilty at the first opportunity and wanted to understand his own behaviour.

Judge Geraint Walters told the court he had “anguished” over Bell’s sentencing.

“I cannot begin to understand how you could have gone from a person of good character during most of your teenage life to committing this catalogue of offences,” the judge said.

He added that Bell “significantly breached his duty” at the In It Together Festival, an annual event whose attendees include teenagers.

After the conviction the Crown Prosecution Service’s Jonathan Pritchard said: “There was compelling evidence to prove that Bell intended to use the festival to supply unlawful drugs, and his mobile phone demonstrated he had downloaded and shared indecent images of children.”