KYIV (Reuters) - Thousands of people silently raised their arms in the air, held flowers aloft and broke into chants outside a church in Minsk on Friday at the funeral of a Belarusian protester.The death of 31-year-old Roman Bondarenko has become a flashpoint in months-long mass protests against President Alexander Lukashenko. Witnesses said Bondarenko was detained after a scuffle with people in plain clothes who came to a playground to remove red-and-white ribbons representing the protest movement. He died in hospital last week after what protesters say was a severe beating by security forces. The interior ministry denied responsibility. The death was condemned by the European Union who on Thursday announced new sanctions on Minsk in response to state repression against protesters following a disputed August election.Opponents accuse Lukashenko of rigging the election to extend his 26-year grip on power. He denies electoral fraud and, backed by Russia, has refused to resign. The crowd outside the church, the majority wearing masks, chanted “I’m going out”, the last known written words of Bondarenko, and “long live Belarus”. Cars blared their horns in the street. Thousands broke into applause as the coffin was carried out of the church. Mourners, some in tears, gathered at the burial site.The authorities this week detained a medic who leaked a medical report of Bondarenko’s death to the media. The medical report showed there was no alcohol in Bondarenko’s bloodstream, casting doubt on the government’s assertion that Bondarenko had been drunk and died in a scuffle with civilians. The Prosecutor General’s office has opened a criminal investigation into the medic for revealing medical secrets, spreading false information and fuelling tensions in society. A journalist who published the report was also detained. Lukashenko accused the protesters of gathering at the funeral against the wishes of Bondarenko’s family, and of fanning tensions by spreading fake reports about Bondarenko’s death on social media. After the EU’s latest sanctions announcement, non-EU member Norway said it would adopt similar measures.United Nations human rights experts said on Thursday they were gravely concerned by increased reports of mass detentions, intimidation and torture. They urged Belarusian authorities to investigate the excessive use of force and unlawful retaliation at peaceful protests. Tens of thousands of people have staged regular protests for weeks since the election. Some workers at major state-run companies went on strike. This week, potash producer Belaruskali said 49 workers had been fired for taking part in the strike.