KYIV - Ukrainian authorities raided an influential billionaire's home on Wednesday in what an ally of President Volodymyr Zelenskiy touted as a sweeping wartime clampdown on corruption that would change the country.

Separate raids were carried out at the Tax Office and on the home of former interior minister Arsen Avakov, and a new Customs Service chief was named, two days before Ukraine hosts a summit with the European Union at which Kyiv wants to show it is cracking down after years of chronic corruption.

Ukraine sees Friday's summit as vital to its hopes of joining the wealthy bloc, a goal that is more urgent following Russia's invasion, and has also embarked on a political shake-up in which over a dozen officials quit or were sacked last week.

Security officials searched the home of businessman Ihor Kolomoiskiy, one of Ukraine's richest men and a one-time Zelenskiy ally, in what several media outlets said was an investigation into possible financial crimes.

The Security Service of Ukraine (SBU) later said it had uncovered a scheme to embezzle more than $1 billion at oil producer Ukrnafta and oil refinery Ukrtatnafta, companies that Kolomoiskiy used to partly own.

Photographs circulating on social media appeared to show Kolomoiskiy, dressed in a sweatsuit, looking on in the presence of at least one SBU officer inside a large wooden home. Reuters could not immediately verify the authenticity of the images.

Kolomoiskiy could not be reached for comment. He has previously denied any wrongdoing.

David Arakhamia, a senior member of Zelenskiy's Servant of the People party, said the entire management of the Customs Service was set to be dismissed and that notices of suspicion had been served to high-ranking defence ministry officials.

"The country will change during the war. If someone is not ready for change, then the state itself will come and help them change," Arakhamia wrote on the Telegram messaging app.

The government later said Customs Service deputy head Serhiy Zvyahintsev would temporarily take over as its chief.

ZELENSKIY PROMISES NEW REFORMS

Ukraine's long-running battle against corruption has taken on vital significance, as Russia's invasion has made Kyiv heavily reliant on Western support and it needs to carry out reforms to join the 27-nation EU.

Zelenskiy presided over the first major political shake-up of the war last week after an outcry over a corruption scandal involving an army food contract.

Zelenskiy said on Tuesday that more personnel decisions were in the pipeline and that there would be "new reforms" coming that would affect the social, legal and political reality.

He was elected president in 2019 on an anti-corruption ticket and launched a crackdown on wealthy businessmen known as "oligarchs" in late 2021.

The Ukrainska Pravda media outlet said the search on Kolomoiskiy's property related to an investigation into alleged embezzlement of oil products and evasion of customs duties.

Separately, Avakov, the former interior minister, said his home was searched as part of an investigation into a helicopter crash on Jan. 18 that killed 14 people including Interior Minister Denys Monastyrskyi.

He said investigators were looking into the purchase six years ago of a model of Airbus helicopter that was involved in the crash, but that "nothing relevant to the interest of the investigation was found."

  - Reuters