More than 450 people were hurt and around 30 arrested during a huge anti-corruption protest in Bucharest, Romanian police said today, a day after the rally.
Police had used water cannons and tear gas to disperse the protesters as tens of thousands rallied to call on the leftwing government to resign.
Many demonstrators needed treatment after inhaling pepper spray and tear gas, while others suffered blows, hospital sources said. Around 30 police were also injured, 11 of whom were taken to hospital.
Police rejected criticism from the centre-right opposition that its officers had used excessive force, saying its response to violence by dozens of protesters had been "gradual and proportionate".
Austrian Chancellor Sebastian Kurz, whose country currently holds the EU rotating presidency, criticised the clashes, which also saw a cameraman for Austria's public broadcaster injured.
"We strongly condemn the violent clashes in Bucharest where numerous demonstrators and journalists were injured. We expect full explanations," he said on Twitter.
"Freedom of expression and, related to that, freedom of the press are basic freedoms of the EU, which we clearly recognise and which must be unconditionally protected."