(Reuters) – Facebook Inc (NASDAQ:) said on Tuesday it has invested more than $13 billion in safety and security measures since 2016, days after a newspaper reported the company had failed to fix “the platform’s ill effects” researchers had identified.

Social media giant Facebook said that it now employs 40,000 workers in safety and security compared to just 10,000 five years earlier.

Facebook downplayed the effects of Instagram on children and did not respond to employee concerns about how it is being used by human traffickers in developing countries. The Wall Street Journal last week reported that Facebook had responded weakly to employees’ alarms.

In a blog posting, the company stated that safety and security issues were not addressed early enough during product development. We have now fundamentally altered that process.

Facebook claimed that its artificial intelligence technology helped to block over 3 billion false accounts during the first half. More than 20 million false COVID-19 content and vaccine content were also taken out by the company.

According to the company, it has now removed 15 million pieces of false COVID-19 and vaccine content from Facebook and Instagram since it began reporting hate speech in 2017, when it started.