A 14-year-old was kidnapped on her way to school and tortured for 17 hours by two older girls who held a knife to her throat and made her strip while recording the ordeal on their mobile phones.

The acts of 'degradation and violence' towards the terrified teenager were encouraged by two youths - one who arrived at the flat and another who urged on Caylen Candy and Chyanne Powell via social media.

Candy and Powell, now both 18, had been drinking for 12 hours when they went out intending to rob children on their way to school. They came across the victim, who was in her uniform and did not know either of them.

Callous: Caylen Candy (left) and Chyanne Powell (right), both now 18, kidnapped a 14-year-old girl, who had been on her way to school, and subjected her to acts of 'degradation and violence' over 17 hours

She was taken to Powell's flat in Waltham Cross, Hertfordshire, where she was made to strip and was filmed as bits of her hair were chopped off.

The girl also had a knife put to her throat as she was made to shave off her pubic hair, forced to carry out a sex act on herself and to sit in a freezing cold bath.

Her head was pushed under the water for up to 10 seconds on three occasions, her body was written over and table salt poured down her throat, St Albans Crown Court heard last Friday.

Afterwards she was made to clean out the bath and was forced to drink alcohol and smoke.

Prosecutor Michael Speak said Candy and Powell made films, stills and audio recordings. Candy was recorded as saying: 'You will get killed if you snitch us.'

They sent the images to another defendant Sanjay Kalia, 18, who responded with comments such as: 'You lot should f*** her up,' and 'Make the most of it - she is p****'

He went on: 'I would cut her breast. LOL. I would carve my name on her back.'

Sanjay Kalia, 18, was sentenced to five-and-a-half years' detention for his part in the horrendous crime

David Appiah arrived at the flat and was shown photos of the girl naked. He carried out covert texting in the room with Powell. He wrote: 'Make her strip. I am bored.' Powell replied: 'LOL'- meaning 'laugh out loud'.

Appiah went on: 'Or make her do press ups. You are her boss.' He went on: 'She is p****** me off. Make her fully strip.'

He described the girl as 'the worm' and said: 'I don't want to f*** her. I have standards.'

Candy, of Leabank Square, Hackney, was sentenced to six years three months in a Young Offenders Institution after pleading guilty to attempted robbery, assault with intent to rob, kidnap, false imprisonment, two charges of actual bodily harm, causing a child to engage in sexual activity and taking and distributing indecent photographs of a child. She had no previous convictions.

Powell, of Riverpoint, High Street, Waltham Cross, was sentenced to seven-and-a-half years, with a three-year extended licence, after pleading guilty to attempted robbery, false imprisonment, three charges of causing actual bodily harm, causing a child to engage in sexual activity, inciting a child to engage in sexual activity, and taking and distributing indecent photographs of a child.

She had previous convictions for street robbery and for wounding when she bit the top off a female cyclist's finger in Birmingham. The judge imposed the three-year licence after ruling that he found her a 'dangerous offender'. It means she can be recalled to custody for three years after the seven-and-a-half sentence has expired if she is considered a danger to the public.

Kalia, of Macoma Road, Plumstead, south east London, was convicted of incitement to continue false imprisonment. He was sentenced to five-and-a-half years' detention. He had no previous convictions.

Appiah, 21, of New Road, Chingford, was sentenced to eight-and-a-half years in jail, with a three-year extended licence, after being convicted of false imprisonment and causing a child to engage in sexual activity.

Locked up: David Appiah, 21, was jailed for eight-and-a-half years for false imprisonment and causing a child to engage in sexual activity

He had previous convictions for robbery and having a bladed article. The judge also ruled he was a dangerous offender because of his previous convictions for robbery, assault and possessing weapons.

Mr Speak said the victim - who cannot be named - crossed the road near Theobolds Grove station, Waltham Cross, on the morning of September 24 last year and saw the two female defendants, who accosted her.

He said: 'For almost a full day this young girl was subjected to acts of degradation and violence you will find hard to comprehend. It began like a street robbery with Candy and Powell trying to rob her of what she had.'

They had tried to rob another 14-year-old as she walked past Cedars Park, but that girl ran away and got into a passing car.

After that the pair took the schoolgirl to Powell's flat at Riverpoint.

Mr Speak added: 'She said: "All I want to do is to go to school", but they took her to the flat and locked the door, saying once she was inside they were going to hurt her.

'They said: "Why don't you get undressed?" They asked about her bra size and forced her to take off her clothes after they pointed the knife at her throat.

'They began to film the proceedings. They filmed as they forced her to shave her pubic region and made fun of her saying: "You are disgusting",' said Mr Speak.

Asked why they were doing it, they replied: 'It is just a bit of fun.'

The victim was also taken on a shoplifting trip to a nearby Tesco store where the group stole Pot Noodles which Candy and Powell ate.

They then went to Candy's home in Hackney before the girl returned to Waltham Cross with Powell, where the victim's family and the police were looking for her.

At St Albans Crown Court (pictured) Judge Stephen Warner told the defendants their crime was 'humiliating and belittling and showed a callous indifference to a visibly distressed victim who was pleading to be let go'

Powell, who was found hiding in a communal area in the flats, told officers: 'I have looked after her - I have not done anything to her.'

Judge Stephen Warner told them: 'It was humiliating and belittling and showed a callous indifference to a visibly distressed victim who was pleading to be let go.

'What she was subjected to was nothing short of torture - physically and psychologically - done for your amusement and gratification.

'She was treated as an object rather than as a person.'