The work, "HIM" by Italian artist Maurizio Cattelan, has drawn many visitors since it was installed last month. It is visible only from a distance, and the artist doesn't make explicit what Hitler is praying for, but the broader point, organizers say, is to make people reflect on the nature of evil.

In any case, some are angered by the statue's presence in such a sensitive site.

One Jewish advocacy group, the Simon Wiesenthal Center, this week called the statue's placement "a senseless provocation which insults the memory of the Nazis' Jewish victims."

"As far as the Jews were concerned, Hitler's only 'prayer' was that they be wiped off the face of the earth," the group's Israel director, Efraim Zuroff, said in a statement.

However, many others are praising the artwork, saying it has a strong emotional impact. And organizers defend putting it on display in the former ghetto.

Fabio Cavallucci, director of the Center for Contemporary Art, which oversaw the installation, said, "There is no intention from the side of the artist or the center to insult Jewish memory."

"It's an artwork that tries to speak about the situation of hidden evil everywhere," he said.

The Warsaw ghetto was an area of the city which the Nazis sealed off after they invaded Poland. They forced Jews to live in cramped, inhuman conditions there as they awaited deportation to death camps. Many died from hunger or disease or were shot by the Germans before they could be transported to the camps.

The Hitler installation is just one object in a retrospective of Cattelan's work titled "Amen," a show that explores life, death, good and evil. The other works are on display at the center itself, which is housed in the Ujazdowski Castle.

The Hitler representation is visible from a hole in a wooden gate across town on Prozna Street. Viewers only see the back of the small figure praying in a courtyard. Because of its small size, it appears to be a harmless schoolboy.

"Every criminal was once a tender, innocent and defenseless child," the center said in a commentary on the work.

Poland's chief rabbi, Michael Schudrich, said he was consulted on the installation's placement ahead of time and did not oppose it because he saw value in the artist's attempt to try to raise moral questions by provoking viewers.

He said he was reassured by curators who told him there was no intention of rehabilitating Hitler but rather of showing that evil can present itself in the guise of a "sweet praying child."

"I felt there could be educational value to it," said Schudrich, who also wrote an introduction to the exhibition's catalogue in which he says art can "force us to face the evil of the world."

On Friday, a stream of people walked by to view the work, and many praised it.

"It had a big emotional impact on me. It's provocative, but it's not offensive," said Zofia Jablonska, a 30-year-old lawyer. "Having him pray in the place where he would kill people — this was the best place to put it."

Cattelan caused controversy in Warsaw in 2000 when another gallery showed his work "La Nona Ora" — or "The Ninth Hour" — which depicts the late Pope John Paul II being crushed by a meteorite. That offended many in Poland, which is both deeply Catholic and was John Paul's homeland.