Five consecutive days of anti-government protests in Bulgaria have sparked fears in Brussels that the country could become "another Hungary or Poland".
Demonstrators have complained of corruption and joined the country's president in calling for PM Boyko Borissov to resign.
The accusations have prompted concern among some MEPs that Bulgaria will be the next to clash with Brussels over the EU's fundamental values.
"What Europe has to fear, what the European Parliament has to fear is that another Poland or Hungary is coming," said Bulgarian MEP Radan Kanev.
He says that he has raised concerns in the European Parliament over what he says is a "deep rule of law crisis", about "media market capture", the "really brutal party political behaviour of the chief prosecutor's office" which contributes to the overall atmosphere of "political and legal insecurity" in the country.
But another Bulgarian MEP, Andrey Kovatchev, from Borissov's party, has rejected allegations there is any democratic drift in the country.
"We have absolutely no comparison here with Poland or Hungary," he said. "We have full freedom. We cannot have one case where academic freedom, for example, is limited like unfortunately in Budapest with the university. We have total freedom of everybody to express their opinion against Mr Borissov, against the government."
For another Bulgarian MEP, Elena Yoncheva, from the Socialists and Democrats, the whole system is corrupt.
"It is because of corruption that Bulgaria is the poorest country in the European Union," she said.
Yoncheva said Bulgaria loses €11 billion each year because of corruption, according to a European Parliament report.
"We are talking about a country of seven million inhabitants," she added. "Take action, not just talk. Talking, seeing, it's good, but we must take action."