Information from the accounts of more than 65,000 Facebook users in Singapore might have been "improperly shared" with data analytics company Cambridge Analytica, the social media giant said yesterday, as the total number of affected users nearly doubled beyond what was originally estimated.

It has also prompted Singapore's privacy watchdog to step in and look into the matter.

Facebook said in a statement yesterday that the information of 65,009 Facebook users here was likely affected in the growing data breach involving Cambridge Analytica, a political consultancy firm which applies data mining and analysis to elections.

Facebook is now embroiled in a global scandal for its role in the breach, accused of not ensuring the security of its users' personal data. Cambridge Analytica is said to have exploited the data for commercial and political use.

Facebook's chief technology officer Mike Schroepfer said in an update on Wednesday that the total number of people who had their information improperly obtained and shared is now estimated to be 87 million, 37 million more than its initial figure of 50 million people.

The bulk of the affected accounts belong to North American Facebook users, which currently stand at over 70 million accounts which had their data compromised.

The Philippines is next on the list, with 1.17 million affected users, followed by Indonesia with 1.09 million and Britain with 1.08 million.

Singapore's Personal Data Protection Commission (PDPC) is looking into the matter, said a spokesman.

"PDPC is concerned that individuals in Singapore are affected. We are looking into the matter and are in close contact with Facebook," the spokesman added. "Facebook users are encouraged to review their privacy settings in order to control how their information is used or shared."

From Monday, Facebook will also notify users, through a link on their accounts, if they were among those who have had their information shared with Cambridge Analytica.

Mr Evan Dumas, regional director for South-East Asia at cyber-security firm Check Point, said that although the incident has reduced consumer trust in Facebook, people "continue to trade privacy for convenience".

"The reality is we haven't hit an inflection point where consumer confidence is low enough to affect change," he said.

And indeed, when asked about the effects of a campaign to get users to delete their accounts, Facebook chief Mark Zucker-berg said: "I don't think there has been any meaningful impact that we observed."

Similarly, Facebook users here also appear unfazed about the company's treatment of the issue. All 20 of the users The Straits Times spoke to yesterday said they would not delete their accounts despite the privacy controversy.

Student Wang Xi Yu, 19, said: "I would love to delete Facebook, but I can't because of how deeply embedded social media has become for us in society."

• Additional reporting by Esther Koh and Lee Wen-Yi