Three men were stripped of their German nationality by a German tribunal on Wednesday after they failed to disclose the fact that they were members of Turkish Islamist group Milli Gorus. The three naturalized Germans lost their appeal to the administrative tribunal in Wiesbaden against a decision by officials in Giessen, north of Frankfurt. The men will have to hand in their German passports when the deadline for any further appeals expires. Officials said they will become stateless, because they renounced their Turkish citizenship when they were naturalised as Germans. Germany keeps Milli Gorus under surveillance and says it has 26,500 members in Germany, making it the largest Islamist group on German soil. The three men were active in the Milli Gorus chapter in the small town of Limburg. Officials say the men should never have been granted German citizenship because Milli Gorus is hostile to democratic principles. Naturalisation is only available to those who speak German and offer allegiance to the German constitution.