Using her position as a social worker, Sendler regularly entered the ghetto, smuggling around 2,500 children out in boxes, suitcases or hidden in trolleys.
The children were then placed with Polish families outside the ghetto, created by Nazi Germany in 1940 for the city’s half a million strong Jewish population, and given new identities.
But in 1943 Sendler, who led the children’ section of the Zegota organization which helped Jews during the war, was arrested and tortured by the Gestapo.
She only escaped execution when Zegota managed to bribe some Nazi officials, who left her unconscious but alive with broken legs and arms in the woods.
“People who stand up for others, for the weak, are very rare. The world would have been a better place if there were more of them,” Marek Edelman, the last surviving commander of the Warsaw Ghetto Uprising, said on national television.