Wed May 7, 10:37 PM ET
The data on the server includes account numbers, customer names, transaction amounts and transaction types, but does not contain any customer PINS, passwords or user IDs, the company statement said.
"The server is protected by multiple layers of security. The risk of data leakage and fraudulent transactions resulting from the loss of the server is deemed to be low," it added.
The bank, which has a backup of the data, apologized to affected customers, and said none of them would be liable for financial losses from any fraudulent activities.
Asked why the bank took nearly two weeks to confirm the loss, HSBC spokeswoman Vinh Tran said:
"We reported it immediately to the police, and then we did an internal investigation to get more information of the extent of it," she said, before informing Hong Kong's Monetary Authority.
Hong Kong's police said they were treating the case as theft, with investigations still continuing.
(Reporting by James Pomfret; Editing by Ken Wills)
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