UN High Commissioner for Human Rights Zeid Ra'ad Al Hussein joined a global chorus of condemnation against the "hideous crime", after gunmen armed with Kalashnikov automatic rifles gunned down staff at French satirical magazine Charlie Hebdo. They also shot two police officers.
The weekly had been the focus of several attacks since publishing controversial cartoons of the Prophet Mohammed in the mid-2000s.
"I utterly condemn the appalling and ruthless attack on media workers and police officers," Zeid said.
"Freedom of expression and opinion are a cornerstone for any democratic society," he said, adding that "those trying to divide communities on grounds of religion, ethnicity or any other reason must not be allowed to succeed."
That, he warned, would "be playing straight into the hands of extremists whose clear aim is to divide religions and societies."
"With xenophobia and anti-migrant sentiments already on the rise in Europe, I am very concerned that this awful, calculated act will be exploited by extremists of all sorts," Zeid said.
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