The Ukrainian parliament has stripped a celebrated former military pilot and presidential hopeful of her immunity as a politician, sanctioning her arrest on charges of plotting an attack on parliament with grenades and automatic weapons.
Nadiya Savchenko was served a summons minutes after the parliamentary session, where she denounced the Ukrainian government for "killing and dividing" the Ukrainian people.
A court was to consider putting her in custody later in the day.
Critics say the dramatic charges against Ms Savchenko were part of authorities' efforts to get rid of a powerful challenger ahead of the next year's presidential vote.
In Thursday's speech to politicians, prosecutor general Yuriy Lutsenko accused Ms Savchenko of plotting an attack on parliament with hand grenades, automatic weapons and even heavy mortars.
Mr Lutsenko claimed Ms Savchenko was acting in cahoots with Russia-backed rebels in eastern Ukraine to stage a "terrorist coup in the interests of Ukraine's enemies".
He presented wiretapped recordings in which Ms Savchenko discussed smuggling weapons from the east and went over plans for the attacks.
Ms Savchenko said she was aware of being wiretapped, and that she talked about the attacks as a "surrealist political provocation" to mock the government that she said failed the public after Ukrainians staged huge protests that led to the ousting of its former Russia-friendly president in February 2014.
Russia responded to those developments by annexing Ukraine's Crimean Peninsula a month later and has supported a separatist insurgency fighting the government in eastern Ukraine since then.
Ms Savchenko, who has declared plans to run for president in the March 2019 election, is regarded by many as a national hero and a symbol of resistance against Russia.
She was elected in absentia to parliament in 2014, months after she was captured by Russia-backed rebels in eastern Ukraine while serving in a volunteer battalion.
She then ended up in a Russian prison.
In March 2016, a Russian court sentenced her to 22 years in prison, saying she acted as a spotter for mortar fire that killed two Russian journalists in eastern Ukraine.
During her trial she sang the national anthem and raised her middle finger in a show of contempt for Russian authorities.
Russian president Vladimir Putin pardoned her shortly afterwards amid international outrage at her sentence.
She remains popular despite falling out with Ukrainian President Petro Poroshenko's government, accusing it of corruption and incompetence.
"The Ukrainian government is the main evil in Ukraine," Ms Savchenko told booing politicians on Thursday.
"The entire people of Ukraine think so."
She accused Ukrainian authorities of profiting from the fighting in the east, saying that "Ukrainians on both sides want peace".
She also mocked politicians for making an about turn and casting her as an enemy, displaying her Hero of Ukraine's media, the nation's highest award.
Shortly after the vote, Mr Poroshenko thanked law-enforcement agencies in a Facebook statement for "preventing terror attacks and exposing the Russian special operation against Ukraine".
Volodymyr Fesenko, a Kiev-based independent political analyst, noted that Ms Savchenko's arrest came amid exacerbating political tensions.
"Savchenko is very charismatic and unmanageable, and it just so happened that she was isolated ahead of the start of the presidential campaign in which she could challenge many politicians," Mr Fesenko said.
"The story of her plot is a clear symbol of the current anarchy which reflects our political tradition," he added.