MANILA, Philippines — A top United Nations' human rights expert condemned the arrest of journalist Maria Ressa on Wednesday hours after investigative agents served a warrant in the newsroom of online media organization Rappler.

Speaking out on Twitter, Special Rapporteur on Freedom of Opinion and Expression David Kaye said the arrest of the Rappler CEO is a "very serious escalation" of recent events perceived as threats to the free press in the Philippines.

Kaye, a law professor, also called Ressa's arrest a "harassment of media inconsistent with the Philippines' obligations to promote and protect freedom of expression."

"Maria Ressa is one the great global journalist/entrepreneurs and an advocate for and friend to free press everywhere," Kaye wrote in a followup tweet.

"The fact that she is spending the night in jail is simply intolerable," he added.

@mariaressa is one of the great global journalists/entrepreneurs & an advocate for & friend to free press everywhere. the fact that she is spending the night in jail is simply intolerable. — David Kaye (@davidakaye) February 13, 2019

Ressa was taken to the National Bureau of Investigation headquarters in Manila after being served the warrant past 5 p.m. when courts were already closing and could no longer process bail.

She was arrested over a cyberlibel case arising from an article Rappler published in 2012 and updated in 2014 when a new law against cybercrime was already enacted. The case, however, is among several charges recently filed against the news website perceived to be critical of the Duterte administration.

Ressa's camp said that a night court refused to accept the settlement of bail for the libel charge, forcing the journalist to spend the night in detention.

Kaye's statement, meanwhile, is the latest of expressions of alarm coming from bodies attached to the United Nations.

Last month, three special rapporteurs released a joint statement raising concern over moves to have the online news outlet's license revoked.

"As a matter of human rights law, there is no basis to block it from operating. Rappler and other independent outlets need particular protection because of the essential role they play in ensuring robust public debate," said Kaye, along with fellow experts Agnes Callamard and Michael Forst.

Callamard is the UN expert on extrajudicial killings while Forst is the special rapporteur on the situation of human rights defenders.

The Philippines' Department of Justice, meanwhile, denied that Ressa's arrest was an act of suppression of the press, arguing that it was simply procedural. — Camille Diola

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