'Why, Lord, did you remain silent?' Pope asks at Auschwitz

Pope Benedict XVIvisited Auschwitz on Sunday, walking through the gates in the footsteps of more than a millionJews, Poles, Roma, gays and others who were killed at the Nazi concentration camp.

The German-born Pope who was on the fourth and last day of avisit to Poland walked alone and in silence.

But later, he spoke up. "To speak in this place of horror, in this place where unprecedented mass crimes were committed against God and man, is almost impossible and it is particularly difficult and troubling for a Christian, for a pope from Germany," he said.

"In a place like this, words fail; in the end, there can be only a dread silence, a silence which itself is a heartfelt cry to God: Why, Lord, did you remain silent? How could you tolerate all this?"

The death toll at Auschwitz and nearby Birkenau, relatedcamps where the Nazis set up industrial systems to kill people, has never been firmly established.

Butthe estimated toll isat least one million Jews, 75,000 Poles, 20,000 Roma (sometimes known as Gypsies), 10,000 Russianprisoners of war,tens of thousands of homosexuals and others.

The Pope placed a candle before the wall where camp officials executed prisoners.

Benedict met agroup of 32 survivors mostly Catholic in the courtyard, talking to each one.

Healso visited the cell where Polish Franciscan friar Maximilian Kolbe was held.Kolbegave his life to spare a man with a large family in 1941 and was canonized in 1982.

Vatican tries to strengthenties with Jews

Benedict was following inthe steps of his predecessor, Pope John Paul, who was from Poland. Heeven visited John Paul's birthplace, Wadowice.

Benedict had visited Auschwitz before, in1979 withJohn Paul and in 1980 with a group of bishops.

While his visit to Auschwitzwas symbolic,the RomanCatholic Church has been trying to establish better relationships with Jewish people, among others.

On Sunday, Benedict called himself a "a son of that people over which a ring of criminals [the Nazis] rose to power by false promises of future greatness."

Benedict himself was raised in an anti-Nazi family in southern Germany and forced to join the Hitler Youth as a teenager. He wasdrafted into the German army near the end of the Second World War, but deserted in 1945.U.S. forces kept him in a prisoner-of-war camp for several weeks.

'Stand firm,' Pope tells crowd of 900,000

Earlier Sunday,Benedicttold a huge crowd of Poles to "stand firm" in their faith, hope and love, and share it with other people in Europe.

An estimated 900,000people sang andwaved Vatican flags at an outdoor mass near Krakow.

Benedictpleased the crowd by occasionally speaking in Polish.