(CNN) -- Rescuers in Ecuador continued to look Monday for two of four miners who were trapped underground after part of a gold mine collapsed in the southern part of the country.
Authorities have found two of the four dead.
"We hope the other two are alive," said Carlos Pareja, Ecuador's minister of non-renewable resources.
Pareja expressed hope after rescuers recovered the bodies of Paul Aguirre and Walter Vera, chief of the mine. Authorities said the search would continue for the other two miners -- Pedro Mendoza, 28 and Angel Vera, 29, who is Walter Vera's brother.
The four were trapped after a cave in around 3 a.m. Friday in a mine in Portovelo, near Ecuador's southern border with Peru.
On Sunday, Pareja said rescue workers were about 26 feet (8 meters) shy of the site they believe the two missing men might be, according to the Andes news agency.
Jorge Espinosa, the under-secretary of mining development at Ecuador's Ministry of Nonrenewable Natural Resources, said Friday that the caved-in mine contained enough air for trapped miners to breath for five or six days.
A team of the country's most senior mining officials descended deep into the mine to check the progress of efforts to reach the two trapped men, the Ministry of Nonrenewable Natural Resources said on its website.
The miners are thought to be about 500 feet (150 meters) deep.
Large rocks and wood blocks have slowed the progress of rescue workers trying to reach the miners, the state-run news agency reported Sunday.
"There's not far to go, but the distance that remains is the most difficult," he said, according to Andes.
He explained that workers were previously digging through a type of mud. Now they must burrow through hard rock and wood, put inside the mine to help support it, which has slowed their progress.
The gold mine is owned by Minesadco.
The cave-in happened just days after crews in Chile rescued 33 miners trapped underground for more than two months -- in a stunning operation that was watched by the world.