The head of Ukraine's Supreme Court was dismissed from his post on Tuesday after being detained in a bribery investigation which anti-corruption authorities cast as their biggest-ever case.
Kiev has redoubled efforts to clamp down on corruption despite Russia's assault, and doing so is vital to meet the conditions for joining the European Union.
Oleksandr Omelchenko, a prosecutor at the Specialised Anti-Corruption Prosecutor's Office (SAPO), said the Supreme Court's top judge had been detained as part of a suspected bribery scheme and was awaiting a formal "notice of suspicion".
Omelchenko did not identify the judge by name but the court had been led until now by Chief Justice Vsevolod Kniaziev, who could not immediately be reached for comment.
"At this time, the head of the Supreme Court has been detained and measures are being taken to check other individuals for involvement in criminal activity," Omelchenko told a joint briefing with the National Anti-Corruption Bureau of Ukraine (NABU).
An emergency Supreme Court plenary meeting hours later voted no-confidence in Kniaziev and then voted for his dismissal as head of the court. Another judicial body would be responsible for stripping him of his status as a judge.
NABU had announced on Monday that anti-corruption agencies were investigating large-scale corruption in the Supreme Court system, and shared a photograph of piles of dollars neatly lined up on a sofa.
In a statement, NABU said the Supreme Court head was suspected of taking a $2.7-million bribe. The agency's chief, Semen Kryvonos, told Tuesday's briefing it was the most high-profile case involving Ukrainian agencies fighting corruption.
"We are showing through real cases, real deeds, what our priority is: it's top corruption, it's criminal organisations at the highest levels of power," he said.
Kryvonos said the bribe was paid for ruling in favour of the Finance and Credit financial group, owned by prominent businessman Konstiantyn Zhevago, and may be part of a broader scheme to pressure the court. Zhevago has denied wrongdoing.