Members of staff at a youth jail were secretly filmed by a TV investigator abusing and mistreating inmates, a court heard.

Freelance journalist Robert Padmore covertly used a camera for the BBC’s Panorama current affairs programme at Medway Secure Training Centre (MSTC) in Rochester.

Four of the staff - Anthony Dance, Gareth Evans, Matthew Cunningham and Christopher Lomax - have gone on trial accused of misconduct in judicial or public office.

Prosecutor Jennifer Knight told a jury at Maidstone Crown Court: “It is the Crown’s case that each of the defendants while acting as public officers, wilfully misconducted themselves.

“There is no doubt that many of the trainees were extremely difficult to manage. They were children and teenagers whose behaviour had got them into trouble, hence their presence at MSTC.

“The Crown do not suggest the job performed by these defendants was an easy one. The Crown does not suggest there should have been some sort of council of perfection.

“They were all fully trained and understood how to manage the challenging behaviour of trainees, and how and when to use approved restraint techniques appropriately.”

But it was alleged that Dance and Cunningham “behaved aggressively and threateningly towards trainees, both physically and verbally”.

“They each demonstrated a motivation to goad trainees into behaviour which would result in restraints being used and did not carry out those restraints in accordance with the MMPR (Minimising and Managing Physical Restraint) programme,” said Miss Knight.

“Both defendants assaulted trainees causally and frequently.”

Dance, 27, of Brookland Terrace, Lower Horsebridge, Hailsham, East Sussex, Lomax, 36, of Timbertops, Chatham, Evans, 27, of Tintagel Gardens, Rochester, and Cunningham, 37, of Megby Close, Gillingham, all deny the charge.

The centre housed about 70 youngsters between the ages of 12 and 17 who had been either remanded in custody awaiting sentence or convicted of offences.

Security firm G4S held the contract from the centre’s opening in 1998 until July 2016 when it was brought within the public centre to be run by HM Prison and Probation Service.

The Government stipulated that such centres employed the behaviour and restraint system MMPR, using “de-escalation and diversion strategies to minimise the use of restraint through the application of behaviour management techniques”.

Miss Knight said the system emphasised that the use of force on a young person must always be viewed as the last available option.

Panorama launched an investigation at the centre in March 2015, using undercover reporter Robert Padmore.

He undertook a seven-week training course and worked 39 shifts as a secure care officer from October 3 to December 6 that year.

During that time he came into contact with Lomax, a duty operations manager, and team leaders Dance, Evans and Cunningham.

Mr Padmore wore a covert camera at about chest height to film at the centre. There were also a number of CCTV cameras in corridors and communal areas.

They did not cover bedrooms, the kitchen, stairwells or the classrooms in the education centre.

Miss Knight said in November 2015 Dance was filmed holding a 15-year-old inmate in a headlock. Shortly afterwards, Dance put another boy, aged 14, back in his room. The teenager was in pain.

Dance then told Mr Padmore: “He’s got a busted finger and I just kept grabbing it today, fat little ----.”

He went on to describe how much he hated the teenager, saying he would happily break his neck if he could get away with it.

On another occasion, on being told the 15-year-old had squirted shower gel all over his room, Dance said: “I just want to go in there and do him. I can’t tall you how angry I am.”

Miss Knight said Dance swore and threatened he would “------- smash you all over the place”.

When the youth complained about being locked in his room to clean it, Dance told him: “Behave like a ---- and you’ll get treated like a ----.” He adds: “Watch what I ------- do to you.

"Damage anything, watch what happens to you, watch, I will ------- annihilate you.”

He told Mr Padmore he should have “smashed” the boy, adding: “I’m trying my hardest but the thing is I know I’m going to hurt him.”

Miss Knight said Dance threatened to stab the 15-year-old because he was singing a song he did not like. He said of a security wand: “This will go in you. I will do it, I’ve stabbed a trainee before.”

He told Mr Padmore he had stabbed an inmate in the leg with a fork.

While restraining another inmate threatening to self harm, a slap could be heard on footage. He later told the Mr Padmore he had not realised he had been “popped” hit by the youth.

Dance said: “I didn’t, but yeah, I did.” He claimed he had recently assaulted the trainee.

“...smashed him up in the room the other day,” he said.

“He was at the door and went to his room and guillotined him and everything. ---- that, I don’t give a ----. Do you know what, as soon as he stepped I ------- wrapped him.”

Miss Knight said Cunningham told the reporter he had to hurt the 14-year-old so that he would be scared of him.

He explained it would be “textbook” but the moment they reached his room it changed.

On another occasion Cunningham said of the teenager he was “just going to get angry, beat the ---- out of this one, then get into trouble”.

After the trainee, an Arsenal fan, taunted Cunningham about being a Liverpool supporter, the team leader backed him into a corner.

He then made him shout louder and louder that he loved Liverpool and Arsenal were ----. After being pushed down into a corner he was in pain and begged Cunningham to stop, saying: “I’m sorry, Matt.”

The boy later told him he was supposed to be a role model. Cunningham replied: “Not for you, I’m in here to hit you, that’s my job.”

The trial continues.