SINGAPORE - A serial cheat who conned retailers of more than $1 million in jewellery and technology goods using an "offline transaction" scam was on Tuesday sentenced to six years of corrective training - a tough prison regime for repeat offenders without remission for good behaviour.

Teo Ziqi, 31, then either pawned or resold the items, including gold bars and iPads, and used some of the proceeds to gamble. Only $140,200 was recovered, a court heard.

Handing retailers his debit card to pay for purchases, Teo would request that the transactions be cleared offline, a process that requires the merchant to seek authorisation from both its own and the customer's bank.

Taking advantage of his victims' unfamiliarity with the correct procedure, he would provide them with an "approval code" purportedly given to him by his bank, sometimes pretending to call the bank for the six-digit combinations in front of staff members.

Keying these in after Teo's card was swiped would result in charge slips being printed out, leading merchants to think that the transactions had been approved.

Teo, then an undisclosed bankrupt, would sign the slips and walk out with the loot.

He pleaded guilty to 23 charges, 20 of which were for cheating or trying to cheat. Some 13 other various charges, including that for forgery and failing to pay a levy to enter the two casinos here, were taken into consideration.

For each count of cheating to induce his victims to hand over property, he could have been jailed for up to ten years and fined.