One of the winners of this year's Nobel Peace Prize has attacked US internet companies for what she called a "flood of toxic sludge" on social media.
During her acceptance speech in Norway, Philippine journalist Maria Ressa said technology giants had "allowed a virus of lies to infect each of us".
Ms Ressa, co-founder of the news site Rappler, accused sites such as Facebook of profiting from spreading hate.
The 58-year-old was addressing guests at a ceremony in the capital, Oslo.
She went on to accuse US internet giants of being "biased against facts and journalists" and of using their "God-like power" to sow division.
"Our greatest need today is to transform that hate and violence, the toxic sludge that's coursing through our information ecosystem," she said.
Facebook's parent company, Meta, recently announced that it was introducing new features to give people more control over what appears in their news feeds. The social network has been under intense scrutiny in recent years for how its algorithms promote content.
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Ms Ressa was receiving the Nobel Peace Prize at Oslo City Hall on Friday along with her co-laureate Dmitry Muratov, editor of the Russian newspaper Novaya Gazeta.
They were both awarded the prize in recognition of their fights to defend freedom of expression.
Mr Muratov, 60, urged guests at the ceremony to observe a minute's silence for journalists killed in the course of their work, and said the profession was going through "a dark time" in Russia.
He said more than 100 journalists, media outlets, human rights defenders and NGOs had recently been branded "foreign agents" by Russia's justice ministry. "In Russia, this means one thing – 'enemies of the people'."
Mr Muratov has for decades defended freedom of speech in Russia. He said journalists had lost their jobs, been forced to leave the country and "deprived of the opportunity to live a normal life".
When he was announced as a winner of the Nobel prize in August, the Kremlin congratulated Mr Muratov, with spokesman Dmitry Peskov describing him as "talented" and "brave".
Both journalists are known for investigations that have angered their countries' rulers and both have faced threats as a result of this.