Germany held a state ceremony and observed a nationwide minute of silence yesterday in honor of the 10 people, most of them Muslim shopkeepers, who were shot dead by neo-Nazis during a seven-year killing spree.
Angela Merkel, the chancellor, said the murders, uncovered by chance last November, had brought shame on the nation. She apologised to the families for police errors that critics have blamed on institutional racism.

"The murders were an assault on our country. They are a disgrace to our country," she told a memorial service in Berlin attended by 1,200 people, including relatives of the victims.

The shootings started in 2000 and continued until 2007, targeting small businessmen including a flower seller, a grocer, a kiosk owner and two doner kebab shop managers.

They happened in cities across Germany, from Munich in the south to Rostock on the north coast, and the same handgun was used each time. A German policewoman was also killed.

Police failed to investigate a possible racist motive, instead suspecting that the families might be involved or that the victims had been caught up in illegal activities.

Authorities found out by accident last November that the murders were committed by a terrorist group calling itself the National Socialist Underground and made up of three neo-Nazis who had been on the run for more than a decade.

Two of them, Uwe Mundlos and Uwe Böhnhardt, committed suicide after a botched bank robbery. A DVD claiming responsibility for all the killings was found in an apartment they had used with the third member, Beate Zschäpe, who was arrested.

The discovery of the trio was a major embarrassment for German security authorities. It exposed them to accusations of having been blind to the threat of far-right violence and preoccupied with Islamist militants since the September 11 attacks.

A parliamentary inquiry has been set up and steps are underway to improve coordination among national and regional intelligence authorities. But critics say deeper change is needed, not only in the organisation of the security services but in the mindset of the police.

"Some of the relatives were themselves under suspicion for years. That is terrible. I ask your forgiveness for that," said Mrs Merkel. "These years must have been a never-ending nightmare for you," she said.

For years, the murders were dismissively referred to by the media and the police as the "Doner Killings" because of the stereotype of Turks running kebab shops. The relatives were given little attention.

"Indifference has a creeping but disastrous effect," said Mrs Merkel. "It drives rifts into our society."

Turkish immigrants and their descendants make up most of Germany's almost four million Muslims. Even though the community dates back more than half a century, they are still labelled as "foreigners" by many Germans, and live in parallel communities.

For some, the memorial ceremony was overshadowed by criticism from immigrant groups that the government is not doing enough to fight racism, and by warnings from police that there are further potential terrorists in the country's far-right, which contains 10,000 people categorised by law enforcement as potentially violent.