At least 78 people have died after authorities imposed a blockade on an illegal gold mine here, part of a monthslong standoff between prospectors and a government determined to force them to surface—often by cutting off their food and water.

Police ended a rescue operation at an abandoned gold mine on Wednesday and said they believe they have brought out all the survivors and retrieved all the bodies after hundreds of miners were trapped for months in one of the country’s deepest mines while working illegally.