The miners sent their rescuers a handwritten message that said all of them are alive and in a shelter, said Chilean President Sebastian Pinera. The note was tied to a probe authorities had lowered earlier on Sunday.

"Now we know the most important thing is that they are alive," said an elated Pinera, who spoke outside the mine.

Cheers erupted around the president as relatives and friends of the miners shed tears and shared hugs. The workers have been trapped since the mine caved in on August 5.

Andres Sougarret, who is in charge of rescue operations, said he hoped to make further contact with the trapped miners later on August 22, though he warned it could take as long as four months to get them out.

The miners are thought to be inside a small shelter 2,300 feet underground that would have had some water and food supplies.

Because of the mine's depth, and the instability caused by the collapse, rescue workers will need to proceed slowly and with caution.