Facebook set up a " war room" to stem the tide of hate speech, false information and other damaging content during Brazil's election this month.
While the company said it was able to thwart false information on its main social network, it's had more trouble controlling misbehavior on WhatsApp, which is encrypted and virtually impossible to monitor.
Reacting to the report, WhatsApp announced Friday that it was taking "immediate legal action to stop companies from sending bulk messages".
Volunteers search for clues in the missing Wisconsin teen case
Evidence suggests Jayme was home at the time of their murders - but she is not considered a suspect. Deputies discovered Jayme Closs' parents fatally shot in their home in rural Barron.
Bolsonaro, a former army captain, won the first round on October 7, getting 46 percent against 29 for Fernando Haddad of the Workers' Party that governed Brazil between 2003 and 2016.
Bolsonaro has denied any knowledge of such a scheme and called on any supporters doing so to stop.
With a career untainted by major corruption investigations, he has rallied voters fed up with years of graft scandals and economic mismanagement while the Workers Party was in power. Mr Bolsonaro wrote on Twitter that his opponent's party "isn't being damaged by fake news, but rather by the TRUTH".
Silhouettes of mobile users are seen next to a screen projection of Whatsapp logo in this picture illustration taken March 28, 2018. Meanwhile, the head of Bolsonaro's PSL party, Gustavo Bebianno, said he did not know the businessmen suspected of making donations.
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The hope is that in addition to providing lighting, the creation will also draw more tourists to the city. The moon , which would actually just be a glowing satellite, will reflect sunlight back to Earth.
A large part of that comes from Bolsonaro's choice to be his economy minister: Paulo Guedes, a US-educated liberal economist who has talked of reducing Brazil's notoriously protectionist policies, selling off state assets to reduce the public debt, and streamlining taxes.
WhatsApp confirmed that it had blocked Flavio Bolsonaro's account for "spam behaviour" in recent days, for reasons unrelated to the Folha report.
The tech company said previously it had banned hundreds of thousands of accounts inside Brazil found to have engaged in spam or automated "bot" behavior ahead of the election. It also noted that it banned an account related to former Brazil president Dilma Rousseff, a member of the Workers' Party.
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Svitolina broke in the sixth game and held her nerve to claim just her second victory against Kvitova from nine meetings. Kvitova's trademark firepower moved Svitolina around the hard court but the Ukrainian's defence was up to the task.