Former Georgian Prime Minister and opposition party leader Giorgi Gakharia has been treated in hospital after he came under attack at a hotel, reportedly by members of the ruling Georgian Dream party.

Gakharia is said to have suffered a broken nose in the incident in Batumi on the Black Sea coast. His party said it was “politically motivated” and aimed at intimidating the opposition.

The southern Caucasus state has seen political turmoil and repeated attacks on opposition figures and protesters in the months since Georgia’s contested elections in late October.

Protests have taken place every night since Georgian Dream’s leaders announced a month later they were freezing the issue of opening talks on joining the European Union.

Hundreds of businesses took part in a three-hour strike on Wednesday on the 49th day of protests in a row.

Video of the incident late on Tuesday night in the Sheraton hotel lobby in Batumi was unclear, although Gakharia could be seen being forced to the floor by a group of men. Images showed him later with blood on his shirt.

Giorgia Gakharia posted on social media on Wednesday morning that “healthwise I’m doing fine”, but the doctor who treated him said he had fractured a bone in his nose and had concussion.

European Commission spokeswoman Anitta Hipper said the “reported involvement of Georgian Dream politicians in the brutal attack” was shocking, and there was no place for violence or impunity in any democracy.

However, Georgian Dream figures have accused Gakharia of initiating the clash himself. MP Levan Machavariani told reporters everything was clear from the footage, while Tbilisi Mayor Kakha Kaladze said the opposition’s agenda was based on lies and deceit.

An MP with Georgian Dream and other members of the party have been linked to the assault, which took place shortly after Zviad Koridze, a journalist and regional head of anti-corruption organisation Transparency International, also came under attack.

Koridze had been visiting Batumi to cover the trial of a leading media figure, Mzia Amaghlobeli, the founder of independent online outlets Netgazeti and Batumelebi.

She was ordered into pre-trial detention in the Black Sea coastal city on Tuesday two days after her arrest during a heated argument with a policeman in which she is accused of slapping the officer. A cameraman was also arrested.

The UK’s ambassador to Georgia, Gareth Ward, said developments in the political crisis in recent days had been “extremely worrying”. “Renewed violence against opposition politicians and arbitrary detention of journalists and protesters is unacceptable,” he said.

Gakharia is not the first opposition leader to face violence in recent weeks. Nika Gvaramia, who heads Coalition for Change, was knocked to the ground unconscious when he was detained in the capital, Tbilisi, last month.

Dozens of Georgian journalists and protesters have also been attacked and injured by pro-government thugs during the nightly protests.

Georgian Dream has been accused by the EU and US of democratic backsliding, and opposition groups accuse the party and its billionaire founder Bidzina Ivanishvili of pursuing Russia’s interests, while the vast majority of Georgians want to join the EU.

Giorgi Gakharia was formerly a leading member of Georgian Dream until 2021 serving as interior minister and then as prime minister, before setting up his own For Georgia opposition party.

In a statement, Georgia’s ombudsman Levan Ioseliani condemned the attacks on both Gakharia and Zviad Koridze. He called for an immediate response “so that attacks on politicians and journalists are not incited”.

Gakharia’s party was one of four opposition groups that secured seats in the October elections, but they all refused to take up their seats, accusing the ruling party of rigging the vote.

The European Parliament has called for a re-run of the election, describing it as neither free nor fair, and the EU’s foreign policy chief Kaja Kallas has accused the government of using repression against the opposition.