MANILA - Facebook has removed over 100 pages and accounts in the Philippines, including several linked to President Rodrigo Duterte, that it said violated its policies on spam.

The social networking giant said in a statement posted on Monday (Oct 22) that it deleted 95 pages and 39 accounts "for violating our spam and authenticity policies".

It said the pages and accounts, which were mostly political or entertainment-themed, directed visitors to "low quality websites that contain little substantive content and are full of disruptive ads".

One page had about 4.8 million followers.

"All were sharing links to the same advertising click farms off Facebook… We don't want this kind of behaviour on Facebook - and we're investing heavily in both people and technology to keep bad content off our services," it said.

Among the pages that were removed by the company were "Duterte Media", "Duterte sa Pagbabago Bukas" (Duterte for Tomorrow's Change), "DDS", "Duterte Phenomenon" and "DU30 Trending News".

All professed backing for Mr Duterte, 73. But it could not be ascertained whether the administrators of these pages were actual supporters of the president or were just profiting off his popularity.

"Manang Imee", a page managed by supporters of Ilocos Norte Governor Imee Marcos, 62, the eldest daughter of the late dictator Ferdinand Marcos, was also removed.

Ms Marcos is a close political ally of Mr Duterte.

"This takedown is a small step in the right direction, and we will continue working to find and remove more bad content," said Facebook.

In April, Facebook blocked a number of websites that supported Mr Duterte but which were suspected of spreading fake news.

At least 20 confirmed sites with links from pro-Duterte Facebook pages were blocked, with notices citing security issues.

The websites carried bogus reports designed to help Mr Duterte. One claimed that Chinese President Xi Jinping had promised in a recent speech to defend him for pulling the Philippines out of the International Criminal Court.

Facebook's recent crackdown on spam networks in the Philippines comes five months before the country holds its midterm elections.

Over 18,000 candidates are seeking national and local seats, in what is seen as a barometer of public support for Mr Duterte.

Facebook and other social media apps played a key role in getting Mr Duterte elected into office.

A recent study by the University of Oxford found that his camp spent about US$200,000 (S$276,000) to mobilise an army of "keyboard warriors" who turned him into the "undisputed king of Facebook conversations" during the 2016 elections. He was the subject of 64 per cent of all Philippine election-related conversations on the site.

Facebook has 33 million users in the Philippines.

Facebook's tougher line on fake news comes amid issues on the company's efforts to protect users' data, as well as accusations that the platform has been used as a tool to influence elections and imperil democracies through the spread of false and divisive content.