Hundreds of neo-Nazi sympathisers have demonstrated outside a jail in Berlin calling for the release of the singer of an outlawed far-right rock group.
The Neo-Nazi sympathisers were demanding the release of a German rock star
Michael Regener was jailed more than three years ago after a court ruled that the band, Landser, was a criminal organisation spreading racial hatred.
Earlier in a newspaper interview, the Israeli ambassador to Germany said he was concerned for Jews in Germany.
Shimon Stein said he thought anti-Semitism was increasing there.
Speaking to the German newspaper the Neue Osnabruecker Zeitung, he said the number of neo-Nazis had also risen and there was a greater willingness to use violence.
Mr Stein said there had tightened security had been put in place around synagogues and other institutions.
"I have the feeling that Jews in Germany do not feel safe. They are not always able to practice their religion freely," he said.
Saturday's protest outside the Tegel jail passed off without any violence.
About 750 neo-Nazi sympathisers took part in the demonstration, which was sponsored by the far right NPD nationalist party.
Several hundred anti-Nazi protesters, some of them elderly people, also turned out and joined chants of "Nazis out".
In March 2005, a German court rejected an appeal by Michael Regener - aka "Lunikoff" - to have his sentence repealed.
Germany has strict laws against promoting Nazism or using Nazi symbols.
Michael Regener was convicted of spreading racial hatred
Three years ago, a Berlin court found the band Landser - meaning "foot soldiers" - guilty of spreading hatred of Jewish people and foreigners in Germany.
The BBC's correspondent Steve Rosenberg says that in recent days German politicians and German police have expressed concern at the rise of the far right in Germany.
There has been a sharp increase in the number of racist attacks carried out by right-wing extremists, says our Berlin correspondent.
The NPD has made significant gains in recent regional elections.
It now has seats in three regional parliaments in Germany.
This week, Germany's coalition government promised to spend more money on the fight against right-wing extremism.