Thousands of protesters have taken to the streets of the Armenian capital after Azerbaijan launched a full-scale military assault on the disputed region of Nagorno-Karabakh. The demonstration came amid rising discontent with Armenia’s prime minister, Nikol Pashinyan, the inaction of Russian peacekeepers and the failure of western governments to stop bloodshed. The announcement of a ceasefire in the disputed enclave on Wednesday appeared to involve the de facto capitulation of local defence forces and looked set to fuel the political unrest in Armenia, piling pressure on Pashinyan. Protesters smashed the windows of government buildings on Yerevan’s central Republic Square late on Tuesday as they scuffled with police in an attempt to get inside. Security officers responded by throwing stun grenades into the crowd. “If we had good leadership, we would be able to resist what is happening,” said Sarhat Petrosyan, an architect and former member of Pashinyan’s government who was out protesting. “All these people are ready to go and fight.” “If he [Pashinyan] can’t do anything, he should resign,” said another protester, Svetlana Abramyan, a pensioner. “He’s a coward.” Dozens of civilians and troops were killed and wounded in the mountainous South Caucasus region, according to local officials, in what Baku said was an “anti-terrorist operation” to dismantle the longstanding Nagorno-Karabakh government and eliminate “illegal Armenian military formations”. Azerbaijani officials said they had reached a ceasefire agreement involving the withdrawal of all local defence units from Nagorno-Karabakh and the surrender of arms and heavy equipment. Many in Yerevan believe that Baku’s ultimate goal is to ethnically cleanse Nagorno-Karabakh, which is internationally recognised as Azerbaijani territory, of its predominantly Armenian population estimated to number about 120,000. “What is going on is an Armenian genocide,” said Yuri, a protester on Republic Square. “It’s a genocide in the 21st century.” A total of 36 people were injured in a night of scuffles between police and protesters in Yerevan, according to the country’s ministry of health. Opposition groups have pledged that demonstrations will continue in the coming days. Pashinyan, who led Armenia through its defeat in the second Karabakh war three years ago, made it clear from the start of the fighting that he did not intend to authorise a military intervention to counter the Azerbaijani offensive. As Russian peacekeepers, believed to number about 2,000 soldiers, appeared either powerless or disinclined to intervene during the 24 hours of conflict, Baku also seemed to rebuff international calls for peace from the US secretary of state, Antony Blinken, and other western diplomats. Some senior Armenian officials have singled out Russian peacekeepers for not doing more to stop the violence. “If Russia wants to stay in the region then it should take some steps to stop [ethnic cleansing and genocide]. If it doesn’t stop what is happening then the answer to the question: ‘Does Russian want to leave the region?’ can only be yes,” said the secretary of Armenia’s security council, Armen Grigoryan, according to local reports. At the same time as the protests on Republic Square, a smaller gathering took place Tuesday night outside the Russian embassy in Yerevan. Several hundred demonstrators chanted “murderers, murderers, murderers!” and blocked Russian diplomats from entering and leaving the building. “Russia provoked the fighting,” said Hayk Hamburbzumyan, a programmer who was standing outside the embassy. “We want to get rid of the Russians once and for all. In 400 years, this is the first time Russia is not as strong as it was. We have an historical opportunity to get rid of them.” Another protester, Mary Papoyan, said: “They don’t want to protect us, they want to control us.” Traditionally strong ties between Russia and Armenia have frayed in recent years as Moscow, mired in its own war in Ukraine, has done little to prevent Azerbaijan tightening its grip over Nagorno-Karabakh – including with a nine-month blockade that led to major food shortages. As tensions in Nagorno-Karabakh rose, Pashinyan appeared to make overtures to the west, and Armenia is hosting a rare joint military exercise with the US. Yerevan’s pro-western course has provoked some anger in Moscow, with the head of the state-owned network RT, Margarita Simonyan, asking mockingly on Tuesday: “What’s up with Nato? Are they not protecting you?” Before the announcement of a ceasefire, the fighting in Nagorno-Karabakh had continued unabated overnight with residents reporting heavy shelling of the enclave’s capital, Stepanakert. Pashinyan’s government is likely to be able to withstand opposition protests as it continues to fully control the security services, according to the Yerevan-based political analyst Tigran Grigoryan. However, any killings or forcible removal of Armenians in Nagorno-Karabakh by Azerbaijan would not only be a consequence of Russia’s unwillingness to intervene, but a failure of US and EU diplomacy, Grigoryan said. “Ethnic cleansing is taking place on their [Russia’s] watch … But if the EU and US don’t act, they will lose all their credibility alongside Russia.”