Facebook has deleted a large number of pages that were used to advertise and sell social security numbers, home addresses and credit card numbers of several dozens of people on its social network.

The move came after the American website Motherboard published reports that hackers had advertised the sale of private user data on Facebook, and that the website kept posts containing that information for years without deleting them.

Following the report, Facebook shares dropped 3.8 percent to $159.58, news agency Hina reported on Tuesday.

“The posts containing information on social security numbers or credit card numbers are not allowed on Facebook, and we remove any such material upon discovery,” Facebook's spokesperson said.

After the Cambridge Analytica scandal in March, which harvested private data from some 50 million Facebook users, tech companies are increasingly scrutinised over their user data protection methods.

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