SINGAPORE - A previous stint in jail did not deter a 59-year-old man from returning to his old ways of drugging his victims and stealing from them.

In 2019, six years after he was jailed for two years over similar offences, Oh Koon Shin struck again. This time round, he targeted three elderly women.

He was sentenced to seven years of corrective training on Friday (Aug 7), after pleading guilty last month to three counts of drugging his victims, two charges of theft and one count of theft in a human dwelling.

Corrective training is a prison regime for repeat offenders without the usual one-third remission for good behaviour. The maximum period is 14 years.

Five other charges - one each of drugging another woman and of fraudulent possession of property, as well as three theft-related ones - were considered during sentencing by District Judge Ronald Gwee.

Court documents state that Oh drugged his victims with zopiclone, a drug used for the short-term treatment of insomnia and which can cause side effects such as sleepiness.

On July 9, 2019, Oh visited retiree Ong Kay Ee at her home, where he offered her zopiclone and convinced her the drug would ease her leg pain.

After taking the drug, the 72-year-old became dizzy and tired, and fell asleep on the sofa in the living room.

Oh then ransacked drawers, and made off with cash as well as jewellery worth $9,000 in total.

He then targeted Madam Ang Poh Choo, 73, at Queenstown Polyclinic on Sept 6, 2019.

Oh approached the bus attendant, who had gone for a medical check-up at the polyclinic, after overhearing her conversation with her friends about her neck pain.

He got her to take zopiclone, saying the drug would ease the pain.

After Madam Ang became light-headed, Oh took her out of the polyclinic and stole from her items such as a gold necklace with a jade pendant worth $6,000 and two gold rings.

He later asked a passer-by to call an ambulance, which took Madam Ang to the National University Hospital (NUH).

Oh's third victim was hawker stall owner Ng Phek Huay, whom he stole from on Sept 9, 2019.

While Madam Ng, 71, was waiting for her turn to see the doctor at Queenstown Polyclinic, he stole money from her handbag.

He then offered her zopiclone and convinced her that she had to take it before her medical check-up.

Thinking that Oh was one of the polyclinic staff, Madam Ng took the drug and became drowsy.

He then took from her a gold-coloured bracelet which she was wearing and took her out of the polyclinic.

Oh then got a taxi to take Madam Ng to NUH, as she was losing consciousness.

On Friday, District Judge Gwee backdated Oh's sentence to Sept 12 last year, when he was first remanded.

For each count of drugging his victim, Oh could have been jailed for up to 10 years and fined or caned.

He could also have been jailed for up to three years and fined for each count of theft.

For his offence of theft in a human dwelling, he could have been jailed for up to seven years and fined.