Bookmaker and gambling site Paddy Power has revealed that it was the victim of a hack that affected 650,000 people.
In a note posted to its website the firm said that customer information was targeted, but not taken. It added that the attack only affected customers that used its pages and services in 2010.
The firm said in a statement: "Paddy Power is contacting certain customers in relation to an historical data breach. No financial information or customer passwords were compromised in the isolated incident and customers' accounts are not at risk as a result.
"The full extent of the 2010 data breach became known to the company in recent months when it took legal action in Canada with the assistance of the Ontario Provincial Police to retrieve the compromised dataset from an individual."
Credit and financial information is safe, according to the firm, but a lot of other information is at risk. The dataset contained customer names, usernames, addresses, email addresses, phone numbers, dates of birth and security questions and answers.
Paddy Power added: "Customers' financial information such as credit or debit card details has not been compromised and is not at risk. Account passwords have also not been compromised. Paddy Power's account monitoring has not detected any suspicious activity to indicate that customers' accounts have been adversely impacted in any way."
Paddy Power said that it is contacting the 650,000 affected customers about the issue, and has also recommended that users change their passwords and security questions on other sites.
Peter O'Donovan, managing director of online business at Paddy Power said: "We sincerely regret that this breach occurred and we apologise to people who have been inconvenienced as a result. We take our responsibilities regarding customer data extremely seriously and have conducted an extensive investigation into the breach and the recovered data."
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