A JUDGE, shocked by the wild behaviour of two teenaged girls who were involved in the assault of a 13-year-old which their accomplice caught on video, placed them on 21-month probation and warned them of harsher punishment if they misbehave again.

Community Court judge Bala Reddy told one of them, 17-year-old Wong Jia Xin, after he had read her probation report, 'This is one of the worst reports I have seen. I am shocked by your background and behaviour.'

The jobless N-Level holder was reported to have had 10 boyfriends so far, and quit her last job as a sales assistant as she felt that her $1,000 pay was too low.

She evaded answering the judge's question on how much salary she would expect with her kind of qualification. Instead, she said she wanted to study to get a certificate and better pay.

Both Wong and Cheng Pei Xia, 18, were each placed on 21 months' probation by the court, which had earlier called for pre-sentence and reformative training reports after they had pleaded guilty earlier this month.

Both will have to observe curfew and do 150 hours of community service. Wong is also required to attend a smoking cessation clinic.

Their parents signed a $5,000 bond to ensure that they behave during the probation period.

Judge Reddy warned them that they would be sent for three-year reformative training if he received any adverse reports on them.

He told Cheng that he would consider reformative training for her if she was unable to hold down a job. She had been job hopping, citing boredom.

The two teenagers had admitted to rioting while being members of an unlawful assembly to hurt the 13-year-old girl at a staircase landing of a block of flats in Pasir Ris Drive 4 between February and March last year.

One of the members had accused the victim of staring but she denied this. The victim, however, admitted to giving a condom to the 21-year-old's ex-boyfriend 'for fun'.

While Cheng, Wong, the 21-year-old and a 15-year-old used their legs and hands to hit and kick the victim, a 15-year-old boy lit a cigarette to time the assault which was recorded on Wong's camera phone by another girl.

The video clip was circulated and was sent to, among others, an 18-year-old student's mobile phone. He made a police report in June last year.