BERLIN — A poster campaign by Germany's Interior Ministry to advertise a hotline for those worried that a friend or family member may be turning to radical Islam has incensed some Muslims who say it stigmatizes them. Germany, home to four million Muslims, has become increasingly concerned about home-grown militants over the past decade after Hamburg served as a base for three of the Sept. 11 suicide airline hijackers in 2001. Officials are especially worried about the ease with which individuals can be recruited over the Internet by extremists. In the new campaign, posters showing four fictitious missing persons – ‘Hassan', ‘Fatima', German convert ‘Tim' and ‘Ahmed' – will be displayed in Arabic, Turkish and German in major cities with big immigrant populations from Sept. 21. “This is my brother Hassan. I miss him and hardly recognize him anymore," one poster reads. “He has become reclusive and gets more radical every day. I'm afraid of losing him completely to religious fanatics and terrorist groups. If you're experiencing something similar, contact the information center for radicalization," it says. Critics fear the1 campaign could fuel stereotypes of Muslims. “Muslims are always regarded as a potential threat," said Aydan Oezoguz, a Turkish-German member of parliament and integration commissioner for the opposition Social Democrats. — Reuters