SOFIA, Bulgaria — Leaked photographs of the prime minister. A police raid on the president’s office. A business tycoon’s takeover of a public beach. A looming no-confidence vote in the government. And the largest street protests in seven years.
Bulgaria is gripped in a political crisis, its biggest since 2013, when sustained protests against corruption brought down a center-left government. Now demonstrators are trying to oust their right-wing successors, who face similar accusations of corruption, judicial interference and servility to wealthy businessmen.
The poorest member of the European Union, nestled on the bloc’s southeastern frontier, Bulgaria is both a focus of the tussle for influence between the West and Russia, and an example of a decline in democratic standards in several parts of the continent.
But it is also a specific and unusual case.
In Hungary and Poland, Europe’s two most prominent victims of democratic backsliding, the governing party is driving the subversion of the democratic process. In Bulgaria, the charge is led by a wider range of actors, both inside and outside the government — including a small group of wealthy businessmen.
The current unrest was set off by the revelation that a stretch of publicly owned coast had been reserved for the private use of a prominent businessman and power broker. For many, this crystallized fears that the Bulgarian state has fallen under the grip of outside influence, prompting tens of thousands to demonstrate in cities across the country.
“There is this sense of having come to a fork in the road,” said Vessela Tcherneva, head of the Sofia branch of the European Council on Foreign Relations, a research group.
“Several things are happening at once,” Ms. Tcherneva added. “But first and foremost, there is the sense in the general public that the social contract, which rests on rules being applied equally to everyone, has been broken.”
The crisis began when an opposition politician, Hristo Ivanov, filmed himself landing a boat on a nominally publicly owned stretch of the Black Sea coast. Plainclothes state security agents shoved Mr. Ivanov back into the water, illustrating how the beach is unofficially reserved for the private use of an influential politician and businessman, Ahmed Dogan.
The episode drew condemnation from the country’s mainly ceremonial president, Rumen Radev, and set off a flood of protests at the influence that wealthy power brokers like Mr. Dogan exert over political life, state resources and, in this case, public land.
“We wanted to expose that the whole state is serving the interests of Dogan,” Mr. Ivanov said in a telephone interview.
Public outrage was quickly compounded when the police later raided the president’s offices and detained two members of the president’s staff. Protesters perceived the moves as retaliation for Mr. Radev’s criticism of Mr. Dogan.
State institutions “have been captured by a group of people to serve their own interests instead of functioning independently as they should,” said Daniel Smilov, an analyst at the Center for Liberal Strategies, a political research group based in Sofia, the Bulgarian capital.
The tension was exacerbated by a steady drumbeat of embarrassing and sometimes bizarre leaks about government officials, including Prime Minister Boiko Borisov.
An unverified photograph recently published in the Bulgarian news media showed him half-naked and apparently sleeping beside a handgun. Another unverified image seemed to show Mr. Borisov’s bedside table stuffed with bank notes and gold bars.
Mr. Borisov has confirmed that the room is his, but he has said that the gun and money are not, and that the images were manipulated.
News outlets have also published a set of recordings of a man who sounds like Mr. Borisov speaking in private about state affairs.
Thousands of Bulgarians have gathered since last Thursday in a central square in Sofia to chant outside Mr. Borisov’s office, calling for his resignation and that of the chief prosecutor.
Last Wednesday, Mr. Borisov tried to assuage them by announcing that he was considering firing three senior government ministers. But he refused to leave his own post — leading protests to spread to other cities.
“People are sick and tired of the collusion between the mafia and the state,” said Neli Trifonova, a 27-year-old online retailer who attended a protest on Monday. “We see it everywhere.”
Opposition lawmakers have put forward a motion of no confidence in the government, which Parliament is scheduled to debate on Monday, though Mr. Borisov’s majority seems likely to hold.
On Wednesday, Mr. Borisov’s party released a statement denying it was working under the influence of Mr. Dogan’s party, which he founded in 1990, after the collapse of communism.
Mr. Dogan’s party, the Movement for Rights and Freedoms, is mainly supported by members of Bulgaria’s ethnic Turkish minority, and has only occasionally been a formal part of government.
But the group and its leading members, like Mr. Dogan, have amassed outsize influence in Bulgaria’s politics, economy and media by consistently performing the role of political kingmakers.
“In Bulgaria, you don’t have a strongman,” said Dimitar Bechev, an expert on southeast Europe at the University of North Carolina at Chapel Hill. “It’s more of an oligarchic system.”
On Monday, the American Embassy issued an unusually forceful statement backing the protests.
“We support the Bulgarian people,” the statement said, “as you peacefully advocate for increased faith in your democratic system and promote the rule of law in Bulgaria.”
The force of the statement contrasted with the less strident tone taken by European institutions and leaders. Some colleagues from the European Parliament’s centrist grouping even issued messages of support for Mr. Dogan and his party.
Though the rule of law is nominally central to the philosophy of the bloc, European leaders have consistently avoided taking too strong a stance against governments that stray from democratic standards at home.
“The E.U. is a mechanism for creating consensus,” Ms. Tcherneva said. “The E.U. is not that good at confrontational situations.”
Boryana Dzhambazova reported from Sofia, and Patrick Kingsley from Berlin.