Philippine journalists immediately attacked the surprise serving of the warrant. She was bureau chief for the U.S. broadcaster in Manila, then in Jakarta.
"This is what journalists in the Philippines now have to go through", she added.
In 2012, she and three fellow female journalists came together to form Rappler, a online news platform with an ethos similar to a tech start-up, operating with a small team of 12 young reporters and developers.
Duterte has a complicated relationship with the news media. Rappler also works as a fact-checker for Facebook in the Philippines in the fight against fake news.
"The NBI has mandate to arrest her that's why they did it". In 2015, during his election campaign, she conducted a now infamous interview with Duterte in which he confessed to killing three people.
Rappler has drawn the administration's ire since publishing reports critical of Duterte's so-called war on drugs that critics say has targeted the poor and could amount to crimes against humanity.
Duterte has made no secret of his annoyance at Rappler and has sparred frequently with its reporters, who are known for scrutinizing his polices and questioning the accuracy of his sweeping, often bellicose statements.
Ms Ressa is CEO of Rappler, a news website critical of the government.
Ressa fully denies the claim, but in August 2017, the Philippine securities and exchange commission (SEC) began what Ressa described as a "six month fishing expedition" demanding hundreds of documents.
Officials first filed the case against her in 2017, but it was disregarded by the National Bureau of Investigation (NBI) because the one-year limit for bringing libel cases had lapsed. While usually such investigations take a minimum of a year, the SEC chose to press charges in just five months.
Rappler CEO and executive editor Maria Ressa talks to her lawyer shortly before her arrest on February 13, 2019. The case is still ongoing.
Ressa, who was named a Time Magazine "Person of the Year" in 2018 for her journalism, left the Rappler offices with plain-clothes officers and surrounded by cameras.
The Philippines tumbled six places previous year in Reporters Without Borders rankings of press freedom to 133rd out of 180, with the body noting the government has pressured and silenced critics.
"It is clear that the Department of Justice perverted the law by charging Maria for an offense allegedly committed before it actually became an offense under the law", NUJP said.
The article included allegations that the businessman was linked to illegal drugs and human trafficking, and that a auto registered in his name had been used by the country's chief justice. Keng had originally filed a lawsuit in 2017 claiming defamation which was it was dropped, but it was refiled again previous year.
Atty. JJ Disini, Ressa's legal counsel, said they will post bail on Thursday morning and will file a motion for reconsideration on the Department of Justice's decision to indict her and Rappler for cyber libel.
Ressa and her publication continued to cover Philippine politics, however, often shining light of incidents of shooting deaths involving individuals, many of them politicians, accused of ties to the drug trade. No court dates or timelines have been set for either the tax evasion and cyber-libel cases.
"If this is another of several attempts to intimidate us, it will not succeed, as past attempts have shown".