SINGAPORE - A United Overseas Bank (UOB) customer service officer unlawfully accessed his employer's computer system so that he could increase his credit card limits, a court heard.

Hong Jingguo, 33, then used his credit card to pay for a flight to Macau and his hotel there, as well as for casino chips at casinos in Macau.

On Tuesday (Oct 11), Hong was jailed for three years and five months.

He pleaded guilty to two charges of unauthorised modification of the contents of a protected computer and one count of converting the benefits of criminal conduct.

He admitted to four other similar charges, which were taken into consideration in sentencing.

A district court heard that Hong's job was to handle UOB customer enquiries, including those relating to customers' credit cards. He earned $3,800 a month.

On three days in June 2014, Hong unlawfully used two UOB call centre team managers' computer accounts to increase his UOB credit card limit temporarily by $12,000, $29,000 and $50,500 respectively.

On two other days later that month, he again unlawfully used these two computer accounts to refund $4,800 and $4,500 to his UOB bank account.

On June 6, 2014, Hong bought three gold bars from Gold n Gems at 61 Choa Chu Kang Drive for $16,800 using his UOB Visa Signature credit card, and then sold them back to the shop for $15,150 in cash. Four days later, he did the same thing.

On Aug 28, 2014, a UOB human resources department vice-president made a police report about Hong's misdeeds.

The total loss suffered by the bank as a result of Hong's actions is $95,291.75. He has since paid back $9,300.

Hong could have been fined up to $100,000 and also jailed for up to 20 years for each of his computer-related crimes.

He could have been fined up to $500,000 and also jailed for up to 10 years for converting the benefits of criminal conduct.