BERLIN (Reuters) - German judges ordered the release of a key accomplice to a neo-Nazi gang which killed 10 people in a seven-year, racially motivated murder spree, saying he had served enough of his sentence to no longer pose a flight risk pending his appeal.

FILE PHOTO: Defendant Ralf Wohlleben, a suspected helper of the neo-Nazi group National Socialist Underground (NSU), arrives in the courtroom in Munich May 14, 2013. REUTERS/Kai Pfaffenbach/File Photo

Ralf Wohlleben was sentenced last week to 10 years in prison for procuring the weapon used to commit nine murders. Beate Zschaepe, one of the gang’s ringleaders, was jailed for life.

His release caused disquiet among Germans who are still shocked by the killings and the lackluster policing in the case. Members of the National Socialist Underground (NSU) killed eight Turks, a Greek man and a German policewoman from 2000 to 2007.

“There could hardly be a harsher blow against the relatives and victims,” said Niema Movassat, a lawmaker for the Left party, on Twitter.

The top security official in Wohlleben’s home state of Thuringia warned that Wohlleben, who was steadfast in refusing to help investigators, would be kept under intensive surveillance.

“He is a hero in that (far-right) scene - he always kept silent,” Stephan Kramer, head of Thuringia’s domestic intelligence service, told RND media group. “We will keep a close eye on him.”

Wohlleben, born in 1975, had a long history of far-right political activity before he fell in with the cell, for whom prosecutors said he was a kind of “guiding spirit” and “mastermind”.

Judges ruled that since Wohlleben had already spent six years and eight months in custody while on trial for crimes including helping shelter the murderers, Uwe Boehnhardt and Uwe Mundlos, he could be given conditional release.

“After the court gave Ralf W. A 10 year sentence last week, he has at most three years and four months still to serve should his conviction be confirmed,” Florian Gliwitzky, spokesman for the Munich higher regional court, said in a statement on Wednesday.

“The remaining sentence is thus no longer enough in this concrete case to make him an exceptional flight risk,” it added.

The murders shook a country that believed it had learned the lessons of its past. A report reut.rs/2m7Xwkw later said police had "massively underestimated" the risk of far-right violence and that missteps had allowed the cell to go undetected.

Boehnhart and Mundlos killed themselves in 2011 when police discovered the gang by chance.

Five of the 10 murders took place in Bavaria. They were the most violent attacks of their kind in Germany since the far-left Red Army Faction’s two-decade killing spree that ended in 1991 and left at least 34 dead.