By Elena Chong & Tracy Sua

THE schizophrenic who poisoned his grandmother and raided her bank account will go to jail and, on his release, be sent to a mental hospital until he no longer poses "a danger to others".

And the grandmother has said she has since forgiven her grandson and told him that, from the start, she had never blamed him for his actions.

Madam Wang Siok Tiang, 75, told Chinese newspaper Shin Min Daily she had been unaware that the 27-year-old unemployed grandson she doted on and cared for was suffering from a medical condition.

Er Choon Sian was yesterday given a 30-month jail sentence and hospital order by District Judge Siva Shanmugam following psychiatrist Tommy Tan's recommendation that he be committed to the Institute of Mental Health after prison as he needed long-term treatment for his chronic disorder.

Dr Tan felt that Er, who had a history of repeated attempts to harm others, was a danger to people, and was likely to miss treatment as an outpatient.

Er yesterday said through his lawyer Sunil Sudheesan that he wanted to pay back the $109,100 he had taken from his grandmother. The court granted the prosecution's application to forfeit this sum from his bank account.

The court heard that Madam Wang had taken Er  in  and cared for him in her Toa Payoh flat after his parents divorced in 1999.

Er's mental condition took a turn for the worse when he was 18 and he was sent to the Institute of Mental Health twice.

But the treatment was of little help and his condition - characterised by paranoid beliefs and bizarre behaviour - deteriorated. The divorce also worsened his mental condition.

The court heard that early last year, Er had planned to harm his grandmother whom he had disliked for some time.

He bought a thermometer, broke it and stored the deadly mercury it contained in an airtight container. He also acquired a bottle of a toxic chemical.

One night when Madam Wang was asleep, he surreptitiously injected a syringe of mercury into her left leg.

About a week later, she fell ill and was admitted to hospital where the toxin was removed from her system. Whether the exposure will result in any permanent disability will  be known only in 18 months to two years' time.

Last July, Madam Wang discovered that debit cards linked to her bank account had been issued without her knowledge and used to make fraudulent withdrawals.

She reported it to police and it was discovered that her grandson had obtained the cards by forging her signature. He was captured on surveillance cameras at ATMs making withdrawals.

Er pleaded guilty last month to seven charges, including the poisoning. Thirty-four other charges were considered.

The judge said there were several aggravating factors in this case: "The offences were premeditated and executed over a period of time."

He said it was clear that Er needed medical and psychiatric help.

When she heard her grandson will be in jail for 30 months, Madam Wang told The Straits Times in Mandarin: "There's nothing much more we can do as he has been convicted. At least he can get his condition treated and get better."

She has not been visiting him in jail recently but recalled that when she last met him while he was in remand, her grandson cried as he apologised to her.

Madam Wang spent months in a wheelchair, but is now able to walk a little. She  says she feels a lot better and does not want to dwell much on the incident.

"Now that he has been sentenced, I just want to put all of this behind me," she said.