MOSCOW (AP) - A Ukrainian court on Friday sanctioned the arrest of a celebrated former military pilot accused of plotting an attack on parliament with grenades and automatic weapons.

Nadiya Savchenko, who has declared presidential ambitions, described the charges against her as an attempt by President Petro Poroshenko's government to get rid of a powerful challenger ahead of the next year's presidential vote.

The Shevchenko District Court in the Ukrainian capital on Friday ordered that she be kept behind bars for two months pending an official probe. The ruling followed parliament's vote to strip her of her immunity as a lawmaker.

Prosecutors have accused Savchenko of plotting a coup in collusion with Russia-backed rebels - a plan to attack parliament with hand grenades, automatic weapons and even heavy mortars.

Savchenko said she talked about attacking parliament as a "surrealist political provocation" to mock the government because she knew she was being wiretapped.

Savchenko told the court Friday that her case was politically motivated.

"When I said I would run for president I became dangerous for the authorities, and they sought to cast me in a negative light," she told the court.

She said she's going on a hunger strike to let the public realize that "the Ukrainian government is just as criminal as the Russian one."

Savchenko became a national hero in Ukraine after spending years in a Russian prison. 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 landed 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 afterward amid international outrage at her sentence, but after her return home, Savchenko quickly fell out with Poroshenko, whose government she has accused of corruption and incompetence.

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