BERLIN // German investigators say raids have been carried out in 600 homes across Austria, Switzerland and Germany. Police suspected that chemicals, used to produce illicit drugs, were being stored in the homes. A statement from state investigators in Bavaria says police raided houses and apartments early on Wednesday morning after a month-long investigation. Investigators were tipped off by suspicious online orders for GBL, a chemical found in industrial cleaners. The legal chemical can be used to manufacture GHB, a potent depressant sometimes refered to as the date-rape drug. The GBL orders were placed to a chemical company near Munich and another in northern Germany.