(CNN) Police and supporters of Nicaraguan President Daniel Ortega retook a major stronghold of the country's anti-government movement Tuesday after storming the suburb and tearing down barricades, Reuters reported.
The clash, which left the Monimbo area of Masaya city in western Nicaragua littered with shell casings and shattered glass, lasted more than four hours and saw protesters armed with homemade mortars pitted against hooded government loyalists with automatic weapons, the news agency said.
The battle was the latest in a series of violent clashes that began in April when the government of the Central American nation announced changes to the social-security system regarding pensions.
Ortega, who fought against US-backed contras during the 1980s and has been in power for 11 years, backed down a few days later, but the government's heavy-handed repression of the protests and the rising death toll ignited a national movement demanding the President's resignation.
At least 273 people have died and 2,000 injured in the unrest, according to the human-rights arm of the Organization of American States (OAS). The government puts the number of victims at more than 50 and argues that the protesters are terrorists and that forces loyal to Ortega are "liberating" towns and cities across the country.
Carlos Trujillo, US ambassador to the OAS, condemned the forceful intervention in Monimbo, describing the government's actions as "genocide."
"The government's repeated acts of violence and repression will only lead to further isolation and sanctions," he wrote on Twitter.
As Tuesday's assault unfolded, Bishop Silvio Báez from nearby Managua tweeted the news and called on Ortega and his government to end the "massacre."
The government said on its website that Monimbo's streets had "been liberated from blockades" and that people can now "move freely," according to Agence France-Presse.
The death toll from months of violence includes two men killed Friday night in Managua in an hours-long attack by pro-government forces on protesters at the National Autonomous University of Nicaragua, the strongest protest holdout in the capital, said Paulo Abrão, executive secretary for the Inter-American Commission on Human Rights (IACHR), part of the OAS.
The protesters, whom the government labeled as terrorists, had sought refuge inside a Roman Catholic church. At least one of them died as the church was hemmed in by gunfire, Abrão said.
Speaking Tuesday, UN human rights office spokesman Rupert Colville called for an immediate end to "the appalling loss of life" in Nicaragua and for protesters' safety to be guaranteed, along with their right to freedom of expression.
His remarks came one day after UN Secretary General António Guterres described the death toll in Nicaragua as "absolutely shocking" and appealed for a political solution to the crisis.
Last week, the OAS held two emergency meetings to discuss the ongoing violence. The organization's secretary general, Luis Almagro, proposed early presidential elections as a way out of the crisis, a suggestion rejected by Ortega's government.