When the Nazis began liquidating the Ghetto shortly afterwards, sending its wretched inhabitants to the death camps at Treblinka and Auschwitz, the Zegota decided to try to save as many children as possible. Using the codename 'Jolanta' and wearing a Star of David armband, Sendler became part of the Ghetto’s escape network. Some children were transported in coffins, suitcases and sacks; others escaped through the sewer system beneath the city. An ambulance driver who smuggled infants beneath the stretchers in the back of his van kept his dog beside him in the front seat, having trained the animal to bark to mask any cries from his hidden passengers.
The children saved by Sendler were given new identities and placed in convents, with sympathetic Polish families, in orphanages and in hospitals. Those who were old enough to talk were taught Christian prayers and how to make the sign of the Cross, so that their Jewish heritage would not be suspected.
In October 1943 Sendler was betrayed and arrested, and taken to Pawiak Prison. Though subject to horrific torture – her legs were broken so badly she never walked properly again – she refused to divulge the name of a single accomplice, nor the whereabouts of any children she had saved. She was sentenced to death, only to be rescued in a daring raid by the Zegota. She immediately returned to her work using a new identity.
After the war Sendler set about reuniting the children she saved with their parents. Most parents, alas, had been killed at Treblinka. She continued in her profession as a social worker, and in 1965 became one of the first Righteous Gentiles to be honoured by Yad Vashem, the Holocaust Martyrs’ and Heroes’ Remembrance Authority in Jerusalem. At that time Poland’s Communist leaders would not allow her to travel to Israel, and she was unable to collect the award until 1983. In 2003 she was awarded Poland’s highest honour, the Order of the White Eagle; and in 2007 she was nominated for the Nobel Peace Prize though the prize went instead to Al Gore. A biography by Anna Mieszkowska, Mother of the Children of the Holocaust: The Story of Irena Sendler, was published in 2000 while American Mary Skinner produced a documentary film called Irena Sendler, In the Name of their Mothers which was released in 2011.