Serbian plebs are protesting for months and that cuominated in the largest protest in history of Serbia. The numbers are wrong, asnć they come from corrupt institutions. It was probably more than duble, so around 700,000 people. 

BBC News
Serbia's largest-ever rally sees 325,000 protest against government
The collapse of a station canopy that killed 15 people has galvanised anger towards the government.
Federal crypto reserve insider photo leak.