Chancellor Angela Merkel attended a memorial service on Saturday for the 21 people killed in a stampede at the Love Parade techno music festival as pressure grew on the local mayor, her party ally, to resign.
"The love parade turned into a dance of death," Nikolaus Schneider, head of the Protestant church in Germany, told 550 mourners in the Salvator Church at the emotional memorial which was broadcast live on four national television networks.
Twenty-one people were killed and more than 500 injured when hordes of young people pushed through a tunnel into the techno festival area at a former freight rail yard in Duisburg, an impoverished western German city of 500,000.
Merkel interrupted her summer holiday to attend the service but criticism of mayor Adolf Sauerland over Saturday's disaster has grown so intense that he opted to stay away.
Sauerland, a leader in Merkel's Christian Democrats, has been assailed for ignoring warnings from city planning agencies, police and fire officials. They had warned Duisburg was too small to host the event with a crowd of up to a million people.
The mayor said he would not resign and was not to blame.
"The pressure on me and my family has been enormous," Sauerland told N24 television in an interview. His family has required police protection.
"I'm terribly sorry about what happened. After an event like this it's easy to come out and demand someone's head. "
There were mistakes made but I'm sure I can help clear up what happened if I stay in office. Answers will be coming."
Flags across Germany were lowered to half-mast on government buildings. At the ceremony rescuers lit candles for the victims.
Many questions, few answers
That such death and chaos could break out in a country like Germany, with its rules and reputation for organizational skills, has prompted national soul-searching and led to angry finger-pointing in Duisburg.
Police said local officials were to blame for ignoring warnings while organizers blamed police for letting too many people into the rail yard.
Some political analysts have warned Sauerland's refusal to step down could hurt Merkel's CDU because it raises questions about the conservatives' credibility on security issues -- ordinarily considered one of their strengths.
Merkel did not speak at the memorial. Hannelore Kraft, state premier of North Rhine-Westphalia and a leader in the centre-left Social Democrats (SPD), said there were many unresolved issues about what went wrong.
"There are too many questions and not enough answers," said Kraft, fighting back tears. Her teenage son was at the Love Parade but not hurt. "How could this happen, who is to blame and who is responsible? These are questions that we have to answer."
Schneider, the Protestant church leader, and Ruhr bishop Franz-Josef Overbeck also spoke critically about the lack of clarity over what happened.
"There were all these young and dynamic people in a party mood and completely confident it would be great evening," said Overbeck. "But then there was chaos, death and injury. It caused pain that will last for a long time."
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