Sixty-five years ago Waclaw Sobczak hid a message in a bottle between the bricks of a wall in a building of the Nazi German Auschwitz-Birkenau death camp, a last sign of life as he prepared to die.

"It was an attempt to leave a trace of our existence as we thought we were going to die," said Sobczak, sent to Auschwitz in 1943 as a slave labourer.

Since, it has emerged that three of the men on the list are still alive.