Heavily armed police raided the offices of Bulgarian President Rumen Radev Thursday, in a move that has exposed political rifts between the president and the country's parliament and oligarchy.

The raids targeted Radev's legal affairs and anti-corruption secretary, along with his security and defense minister. The officials were detained for questioning and their offices searched.

Prosecutors said the raids were part of two separate probes into influence-peddling and disclosure of state secrets.

Protecting the oligarchy?

However, Radev's supporters said the raids targeted the president in order to deliberately delay corruption investigations into Bulgaria's political elite and oligarch class.

Thursday's raids were followed by thousands of people taking to the streets of the capital, Sofia, to denounce the raids and chief prosecutor Ivan Geshev.

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In a short speech in front of demonstrators, Radev called for a "purge" of the "mafia" within the government and the prosecutor's office.

Protesters responded with chants of "Geshev is a disgrace!" and "Out with the mafia!"

Geshev said ahead of the protests that the raids were not part of "political games."

"It does not matter if it is the president or the premier, the prosecution acts on the basis of evidence and does not care about political consequences," he said.

Corruption widespread in Bulgaria

Radev, who was elected in 2015 with the backing of the Bulgarian Socialist Party, is a harsh critic of the Cabinet of conservative Bulgarian Prime Minister Boyko Borisov, accusing him of having "links with the oligarchs."

Last year, Radev tried to block the appointment of chief prosecutor Ivan Geshev amid public outcry that Geshev would do little to tackle widespread, high-level corruption in Bulgaria.

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Radev has also pursued constitutional changes on power limits and improved accountability for the chief prosecutor's office.

Bulgaria is ranked as the most corrupt member state in the European Union by governance watchdog Transparency International.

wmr/mm (Reuters, AFP)