Thirty-three miners who have been trapped underground in a Chilean mine for the past 17 days are all alive, President Sebastian Pinera has said.
Rescuers heard hammering noises when they sent a new probe into the mine.
When the probe came back it had a note tied to it saying: "All 33 of us are fine in the shelter."
The men were working at a depth of around 700m (2,300ft) at the San Jose mine, near the city of Copiapo, when the rock above them collapsed.
Until Sunday, there had been no word from the miners and hopes for their survival had all but faded.
But it could take several months to drill a rescue shaft large enough to rescue the men.
Mr Pinera was at the mine on Sunday when he announced the breakthrough. Brandishing the miners' note for TV cameras he hailed the news saying:
"It will take months to get them out. It will take time, but it doesn't matter how long it takes, to have a happy ending."
President Pinera said he had seen footage of the men waving at a camera inserted into their shelter through a small tube.
"They got close to the camera and we could see their eyes, their joy," he said.
The miners are reported to be 4.5 miles (7km) inside the gold and copper mine and about 700m vertically underground.
They have been trapped since 5 August when the main access tunnel collapsed.
According to Reuters news agency, the authorities said the men are in a mine shaft shelter about the size of a small flat and have limited amounts of food.
Rescuers plan to send narrow plastic tubes down the borehole with food, hydration gels and communications equipment, including cameras and microphones.
However, the chief engineer in charge of the rescue operation, Andres Sougarret, has warned that it will take at least four months and more powerful digging equipment to reach the men.
"A shaft 66 cm (26 inches) in diameter will take at least 120 days," he said.
On Saturday relatives of the trapped men had accused the authorities of not doing enough to reach the men.
One of their complaints was that officials had so far insisted on using probes to locate the miners, rather than digging tunnels through which they could be rescued.
Many of the trapped men's relatives have been camped outside the mine since the tunnel collapse occurred.
There were jubilant scenes as the news that contact had been made broke.
"We never, never lost faith. We knew they were there, and that they would be rescued," one relative, Eduardo Hurtado, said.
"For the first time, I'll be able to sleep peacefully," said the daughter of Mario Gomez, one of the trapped miners.