Close to 650 clients of Standard Chartered's private bank in Singapore have had their information stolen, the bank said on Thursday evening.

The theft was discovered by the police, who informed Stanchart that 647 of its private banking clients' monthly statements had been accessed illegally. The statements were for the month of February this year.

The files were found on a laptop seized from James Raj Arokiasamy, the suspect in the middle of several website hacking incidents, according to a police statement released on Thursday night.

Police discovered the files in the course of their investigations after seizing James Raj's laptop in November.

The police then alerted the bank and the Monetary Authority of Singapore. Stanchart lodged a police report on Monday.

James Raj, who allegedly used the pseudonym "The Messiah" to hack government websites earlier this year, is also currently facing a drug charge.

The theft of the Stanchart banking statements did not occur through the bank's IT and data security systems, said the bank's chief executive for Singapore, Mr Ray Ferguson, at a media briefing.

Instead, the information was stolen from one of the servers of a third-party service provider, Fuji Xerox, which had been hired to print bank statements for Stanchart's private bank clients.

No clients from Stanchart's other banking divisions - including retail, wholesale and small- and medium-sized enterprises banking - were affected. The bank said it has not found any unauthorised transactions resulting from the incident.

Police say they are still investigating.