MANILA (Reuters) - The Philippines' privacy watchdog said on Friday it has started investigating Facebook Inc <FB.O> over a data breach involving British firm Cambridge Analytica that affected more than a million Filipino users of social media.
The move follows a decision by European Union privacy watchdogs to look deeper into the harvesting of personal data from social networks for economic or political purposes.
Outside the United States, the Philippines had the largest amount of user data acquired by Cambridge Analytica, with 1.17 million accounts in the country affected, the National Privacy Commission (NPC) said last week.
In a letter to Facebook founder Mark Zuckerberg, dated April 11, the NPC said it would look into how Facebook shares personal data of Filipino users with third parties, and demand concrete action to protect their data privacy rights.
"We are launching an investigation into Facebook to determine whether there is unauthorized processing of personal data of Filipinos, and other possible violations of the Data Privacy Act," it said in the letter, made available to the media on Friday.
A Facebook spokesperson said the company is committed to protecting people's information and is engaged with the Philippines' privacy watchdog.
"We've recently made significant updates to make our privacy tools easier to find, restrict data access on Facebook, and make our terms and data policy clearer," Facebook said.
Recent research has shown Filipinos to be among the most active social media users in the world, spending on average more than four hours a day on platforms like Facebook.
Facebook has admitted that personal data of nearly 87 million users was improperly accessed by Cambridge Analytica, which has counted U.S. President Donald Trump's election campaign among its clients.
A Hong Kong newspaper has said several people involved in President Rodrigo Duterte's 2016 election campaign had met in 2015 with Alexander Nix, the now-suspended chief executive of Cambridge Analytica.
Those officials said the meeting with Nix was during a lunch break at an information technology seminar in Manila and there has been no contact since.
The president's spokesman said on Tuesday that Duterte's election campaign did not rely on information bought from anybody, nor did it hire Cambridge Analytica's services.
Duterte, a former mayor from outside of the sphere of national politics, successfully tapped Filipinos' insatiable appetite for social media to help him win a 2016 election by a huge margin.
His office uses social media with gusto, courting popular bloggers, in some cases hiring them, to promote Duterte and discredit his opponents, and amplifying the message through "shares" and "likes".
Duterte, however, has said he does not need social media, and on Friday denied any links to Cambridge Analytica.
"Why will I pay those Cambridge fools to work on my campaign? I could have lost with that," Duterte told reporters.
(Reporting by Neil Jerome Morales; Editing by Martin Petty and Eric Meijer)