An American survivor of the 1943 escape from Sobibor Nazi death camp, who has waged a lonely fight to have it preserved as a memorial, returned this week and wept at the sound of Israel's national anthem.

Thomas Blatt, surrounded by a small group of friends, joined them in singing the Hatikvah, or The Hope.They stood next to the grass-covered mound of ashes and bones which likely contains the remains of both of Blatt's parents and of his little brother.

"I could never imagine that I could stand here someday and hear singing of the Hatikvah in this spot," said Blatt, 60, of Santa Barbara, Calif.

"I hope there is another world and that all the people, from Holland, from France (who also died at Sobibor) are listening too," he said.

It was a day of vindication for Blatt. He was accompanied by a Polish official who confirmed publicly that Poland would replace an erroneous sign at the camp's entrance which lists the 250,000 victims as Soviet prisoners of war, Jews, Poles and Gypsies.

"Here the victims were all Jews," said Lee Kagan, president of the Holocaust Sites Preservation Committee, founded by Blatt.

Blatt, a Polish Jew, was 15 when he arrived at Sobibor in April 1943. He watched as his mother, father and brother were marched off to their deaths. He was spared by the caprice of the camp commander, who needed a shoeshine boy.

Six months later, Blatt took part in the camp's successful uprising, in which most of the Nazis were killed and 300 prisoners escaped. About 50 of those escaped prisoners survived the war. The story was the topic of a CBS television movie last year, "Escape from Sobibor."

Blatt survived the war, fighting with partisans against the Germans, and eventually emigrated to the United States. He has revisited the camp many times and has repeatedly protested its unkempt condition and the misleading sign.

Kagan thanked Jacek Wilczur, a historian with Poland's Main Commission for the Investigation of Nazi War Crimes-Institute of National Remembrance, for agreeing to change the inscription.

Noting that Sobibor was the site of the only successful mass uprising at a concentration camp, Kagan said:

"We would like to thank you for restoring a page in Jewish history. There are still people who think Jews went like sheep into places like this. And it's not true. Here, at the site of their biggest revolt, I'd like to thank you."