By Frances Harrison
BBC religious affairs reporter
A Berlin art gallery has temporarily closed an exhibition where one of the posters made fun of Islam's holiest shrine, the Kaaba in Mecca.
The poster was among 22 by the Surrend group
The decision came after threats believed to be from Muslims.
The exhibition was organised by the Danish group Surrend, which said it wanted to oppose religious extremism.
A poster on display showed the Kaaba - the black granite cube-shaped building in Mecca. The words "stupid stone" in German were superimposed on it.
It is toward the Kaaba that Muslims must pray.
The poster - among 22 on display - also showed the faithful walking around it with speech bubbles saying "Zionist occupied government", which referred to the title of the exhibition.
The Danish artists said they wanted to satirise the conspiracy theory that Jews are behind everything - a view they say is prevalent among neo-Nazis and in parts of the Arab world.
The director of the art gallery in Berlin said there had been threats of violence if the poster was not removed, so they had decided to shut for a while.
But he has also expressed concern about groups of individuals censoring art.
The art group Surrend says its mission is to make fun of the world's powerful men and crazy ideological conflicts, using stickers, posters and advertisements.
In 2006 Surrend took out an advertisement in an Iranian daily with a picture of President Mahmoud Ahmadinejad expressing support for his fight against US President George Bush.
It looked harmless, but the text was carefully arranged so that the letters at the start of every line spelled out the word "swine" when read vertically.