One of the freed tourists kidnapped in the Sahara desert said today that his captors had demanded money to buy weapons to overthrow the Algerian Government. No one has claimed responsibility for the kidnapping of 32 European tourists in southern Algeria, 17 of whom were released yesterday. This led to a range of theories blaming Islamic extremists or smugglers that operate in border regions. But Gerhard Wintersteller, a retired technician who led an eight-member group of tourists that went missing in late March, said that the kidnappers "told us they wanted to install an Islamic state in Algeria and overthrow...