Ecuadoran police and soldiers on Tuesday took complete control of a prison where riots between rival gangs killed 68 over the weekend, the head of the prison system said.
After violence broke out on Friday night and stretched into Saturday, with inmates attacking each other with guns, machetes and explosives, authorities described the Litoral Prison in the city of Guayaquil as quiet on Sunday.
Authorities have said the fighting gangs were tied to drug-trafficking organisations.
On Monday, a 1,000-strong security force started penetrating security perimeters around and inside the prison but had not yet entered the wings with the inmates' living quarters, or blocks.
On Tuesday police and soldiers finally moved into that part of the overcrowded penitentiary and called the situation "under control."
"We are intervening inside the blocks," said the head of the prison system, Fausto Cobo.
Another riot in the same prison in Ecuador's south-west in September left 119 dead, making it the largest such massacre in the country's history, and one of the worst in Latin America.
More than 320 inmates have been killed so far in 2021, and the latest riot happened despite a state of emergency enforced in Ecuador's prison system after the riot in September.
Situated between the world's biggest cocaine producers, Colombia and Peru, Ecuador has had a surge in violence blamed on fighting between rival drug groups.
The country of 17.7 million people is popular with traffickers because of its porous borders, a dollarised economy and major seaports for export.