Belarus opposition politician Maria Kolesnikova said security officers put a bag over her head and threatened to kill her when they tried to forcibly deport her to Ukraine earlier this week.
Kolesnikova, a prominent leader of month-long protests against the re-election of President Alexander Lukashenko, prevented the attempt to expel her by tearing up her passport. She is now in detention in the capital Minsk.
She said in the statement that she had genuinely feared for her life.
"In particular it was stated that if I did not voluntarily leave the Republic of Belarus, I would be taken out anyway, alive or in bits. There were also threats to imprison me for up to 25 years," Kolesnikova said.
Her lawyer said she was filing a criminal complaint against Belarusian authorities including the KGB security police.
Lukashenko denies rigging the August 9 election, which official results said he won by a landslide, and has cracked down hard on opponents demanding his resignation.
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