Coalition partners of Czech Prime Minister Petr Necas said they were considering whether they could stay in government with him on Saturday after a court ordered the detention of his close aide on corruption charges.
A court in the eastern city of Ostrava ruled that Jana Nagyova, who had been in charge of Necas's office for years, be remanded in custody. Prosecutors allege she bribed politicians and illegally ordered intelligence agents to spy on people in whom she had a personal interest.
After the court ruling, an official with TOP09, the bigger of two parties in coalition with Necas, said party leaders would meet on Saturday evening to decide what to do about staying in the coalition.
Karolina Peake, leader of the second junior partner in the coalition, the small liberal party called LIDEM, told Reuters: "The situation is becoming more serious from hour to hour."
Necas's office issued a statement saying Nagyova could no longer carry on in her job. But he said he had no knowledge of the offences she is alleged to have committed, and that some of the charges were "nonsense".
He said that when he returned on Sunday from a scheduled trip to Poland he would have a meeting with coalition partners. It could be a showdown that decides the fate of his government.
Necas's Civic Democrat party alone does not have enough seats in parliament to hold on to power, so if either of the junior partners turn against the coalition, he would fall. A new election could follow, or president Milos Zeman could try to pick a new prime minister to form a new cabinet.
The government has been in turmoil since prosecutors charged Nagyova and seven other people as part of the biggest sweep against suspected political corruption in 20 years. Prosecutors said more charges might follow, but declined to give details.
Starting around midnight on Wednesday, around 400 officers, some clad in balaclavas to conceal their identity, raided 31 premises, including bank safe deposit boxes, and seized at least $6 million in cash and tens of kilograms of gold. They did not say from whom they seized the assets.
The court in Ostrava did not rule on the substance of the charges, but by keeping Nagyova in jail it showed it believed prosecutors at least had a credible case. That made it harder for the governing coalition to dismiss the allegations as a witch-hunt by rogue prosecutors.
Nagyova's role is crucial to the prime minister's political survival because, although there are no allegations he was involved, the two have worked very closely together for years.
Outside the court in Ostrava, Eduard Bruna, a lawyer for Nagyova, said she rejected the accusations.
Earlier on Saturday, Czech President Milos Zeman was asked by reporters whether he thought the centre-right cabinet led by Necas should stay in office.
"I consider the charges that have been brought to be very serious," said Zeman, a political opponent of the prime minister.
"After hearing from the chief of police and the supreme state attorney, I am coming to the conclusion that they are based on sufficient evidence."
Czechs are confronted daily with evidence of corruption, including reports about kickbacks paid to government officials and disdain for the law among the wealthy.
The investigation into Nagyova and others appeared to show a new willingness by police and prosecutors to strike at well-connected people.
That may be, in part, due to Necas himself. Under his watch, the government has tried to appoint prosecutors with a free hand to go after sleaze.