PRAGUE — A scandal at Prague’s town hall prompted the Czech Republic’s education minister to resign on Sunday and threatens the stability of the country’s coalition government, which came to power on a promise to root out corruption and to restore liberal democracy.

The Czech Republic will take over the rotating EU Council Presidency next month.

Petr Hlubuček, who resigned as deputy mayor of Prague, spent the weekend in jail after being arrested on Friday evening, one of 11 people linked to the city’s transport company DPP to be charged of corruption, involvement in organized crime and suspicion of illicit drug use.

Hlubuček is a member of the Movement of Mayors and Independents (STAN), the second largest of the five parties forming the national governing coalition. Lobbyist Michal Redl, a former associate of fugitive mafia kingpin Radovan Krejčíř, who is in prison in South Africa, was also arrested.

Education Minister and STAN member Petr Gazdík reportedly had several meetings with Redl. He said he was innocent of any wrongdoing, but resigned to avoid harming the government.

“I don’t want to shake the government or the coalition on the threshold of the EU presidency,” he said. said.

“Petr Gazdík is neither accused nor indicted. It is therefore an honest solution, which we have not been used to in high politics in recent years,” said Prime Minister Petr Fiala. wrote on Twitter. He told state news wire CTK that he was waiting for “clarifications” from STAN.

STAN leader and Deputy Prime Minister Vít Rakušan announced that the party will propose an assembly to vote on its leadership, initially scheduled for the fall.

Hlubuček said he was resigning to prevent “unwarranted political criticism” of STAN by other city council members.

The arrests are rocking the coalition government, which was formed in November after promising to restore faith in mainstream politics among a deeply cynical electorate.

If STAN imploded, Fiala’s hold on power would be threatened. The coalition has 108 seats in the 200-member parliament, but would lose its majority without the 37 MPs from the Pirates Party and STAN.

It would provide an opening for Andrej Babiš, the former prime minister ousted in October’s election after being accused of fraud. His opposition party Ano has 72 seats.

“The real leader of the Hydra is Mr. Rakušan, who covers STAN’s organized crime from the position of Minister of the Interior”, Babiš said. “By leaving Rakušan in government, Mr. Fiala endorses the mafia and STAN’s theft practices.”

The unrest and arrests recall the 1990s and 2000s when the country was mired in corruption scandals.

“It reminds of the dark days,” said Jiří Pehe, political analyst and director of New York University in Prague. “Unfortunately, this seems to be a recurring theme in Czech politics and risks further undermining people’s trust in politics.”

The country’s previous Council presidency in 2009 was undermined when Prime Minister Mirek Topolánek’s government lost a vote of confidence.