PRAGUE, June 4 (CGTN) -- Tens of thousands of Czechs hit the streets on Tuesday to demand the resignation of billionaire Prime Minister Andrej Babis over alleged conflicts of interest involving his former business empire and an investigation into a decade-old EU subsidy.

Organizers estimated that 120,000 people protested on Prague's central Wenceslas Square, making it one of the largest demonstrations in recent decades.

Protests against Babis have swelled since the end of April just as Czech police concluded investigations into whether he illegally received a 2-million-euro EU subsidy for a farm and convention center a decade ago and recommended he face trial.

Protesters fear a newly appointed justice minister could interfere in the case, now in prosecutors' hands. Babis has denied wrongdoing, calling the case a political maneuver.

The anti-Babis movement received further impetus from a leak of preliminary audit findings by the European Commission which determined that Agrofert – a business empire built by Babis and spanning chemicals, food processing, farming and media firms – should not have had any access to EU development funds in recent years because Babis had conflicts of interest.

“We will not act like it is normal that the prime minister of our country remains ... in such a conflict of interest that his personal problems damage the whole country,” organizer Mikulas Minar told protesters from a stage just below the imposing 19th-century National Museum.

“We are asking for the resignation of Andrej Babis.”

Demonstrators filled the 700-meter-long rectangular Wenceslas Square, scene of some of the most politically momentous gatherings in Czech history.

Waving Czech and EU flags, protesters carried signs saying “We've had enough!” or “We don't want Babisstan.”

Babis is the second richest Czech with 3.7 billion U.S. dollars in assets, according to Forbes magazine.