A THIRTEEN-year-old girl who committed suicide last week had been dabbling in the occult, according to her head teacher, and left a note detailing a nightmare about a ''shadow in red'' before she jumped to her death. The revelation comes amid new evidence that a disturbing number of teenagers are becoming emotionally unbalanced after using ouija boards, resulting in some schools calling in an ''exorcist'' to ''cast out evil spirits''. Wong Oi-man, a Form One student at St Stephen's College, leapt from her 10th-floor flat last Sunday. The headmaster at her school, Luke Yip Jing-ping, said he had received reports the girl had been using a ouija board. ''I did not find out until after her death,'' said Mr Yip. ''I was told she dabbled in occult games as recently as last month. Some students said she did this frequently. ''She was a cheerful girl, happy-go-lucky. It was a real shock. We never thought a child like her would commit suicide.'' Oi-man apparently told those close to her she had been haunted by nightmares. In her suicide note, she spoke of a ''death dream'' she had two days before her death. She also mentioned a conversation she had had with a ''shadow in red''. ''I woke up from my dream and I saw it,'' she wrote. ''It said: 'big girl, can you hear me?' and I replied 'yes'.'' Oi-man said she was asked by the ''shadow'' whether she wanted to kill herself or ''let us kill you''. ''I said I would kill myself,'' she wrote. ''I asked why it wanted me to die. The shadow said it did not know.'' Oi-man said the figure later told her it had been asked to go to her at midnight by somebody. ''I asked who that somebody was. The shadow said it was a secret,'' she wrote. Mr Yip warned of the dangers of ''occultism''. He said: ''Whether or not her death is directly linked to these 'games', occultism should not be publicised. ''The media is to blame. Television and radio stations have been promoting the supernatural. Some students are too young to determine whether or not there are such things. Can you imagine the mental turmoil they go through? ''They are confused but they don't seek clarification. By the time you find out, it is already too late. Why do the media confuse these students? Why do we promote the idea that one should place one's lives in the hands of someone else? Why do we promote fatalism? ''Oi-man did not strike us as suffering from any psychological problems. She was a happy child driven by an urge beyond reason; a nightmare. She was consumed by a thought. She never told anyone she wanted to die. Imagine a bright child having to go through that. It is very sad.'' Another headmaster, who declined to be named, said his school had a problem with occult practices among pupils. He said one girl had become ''possessed'' by evil spirits and that he and a group of Christian teachers had held a secret exorcism in the school library. ''The girl just suddenly went mad in the classroom, as if she was a different person . . . We decided to take her to the library. We first tried to reason with her, but it did not work. We then started praying for her,'' said the headmaster. ''I am a Christian. We believe she was possessed. We thought the only thing we could do was to exorcise her. We prayed for her. We also demanded the demon leave her in the name of Jesus Christ. ''She went completely out of control when we said the word 'Jesus'. One of the teachers gave her a glass of water and she started biting the glass. It took three of us to control her and take the pieces of glass out of her mouth. ''You had to see it to believe it. I can still remember the way she looked at me: she was so different, so hostile.'' The school priest was later called in to help, and with the help of the teachers he managed to ''exorcise the spirit'' from the girl, he said. The following day, an ''exorcist'', Danny Ma Kwok-tung, was called in to make sure the girl was no longer possessed. The headmaster said the girl regularly took part in occult games, and had tried to kill herself at a schoolmate's flat. ''Just days before the incident in school, the girl was playing occult games at a friend's. I was told her character changed suddenly and she began talking in a strange voice. She threatened to jump out of the window,'' he said. ''Exorcist'' Mr Ma, associate general-secretary of the Hong Kong Christian Short-Term Mission Training Centre, said he had come across a number of cases of students being ''possessed'' after dabbling in occultism. He said he was called in by schools because he had achieved good results. ''If you play those games there is a good chance that you are exposing yourself [to evil spirits],'' he claimed. ''I have come across one student who attempted to kill herself by slitting her wrists. Another had to be rushed to hospital with his hands bound because he went completely out of control,'' he said. Mr Ma said he considered himself qualified to perform exorcisms because ''according to the Bible, every Christian can perform exorcisms''. But he said: ''I know some students may only be psychologically disturbed. That is why we have to consider all factors before we start work.'' He said the problem of students dabbling in the occult was becoming more serious. Random surveys have shown at least 10 per cent of Hong Kong students have used ouija boards. A recent Hong Kong Federation of Youth Groups survey showed 50 per cent of young people have engaged in some kind of fortune telling or related activities, and one in 10 has made contact with spirits. The survey of 530 people aged between 10 and 24 also showed many students did not believe in such practices, but took part out of curiosity, for fun or because of peer pressure. Lisa Yip Sau-wah, headmistress of Sha Tin Tsung Tsin Secondary School, said: ''They might not believe in it . . . but they would still play the games. They just don't know what they are getting into. They believe they are strong enough to handle anything, but they can turn out to be quite weak. She said she considered the problem widespread in schools among students of all ages. ''If I found out that any my students were playing these games,'' she said. ''I would seriously try to discourage them. I would tell them as a Christian I believe evil spirits do exist - and it is extremely unwise to make contact with them.''