ISTANBUL (Reuters) - Kurdish rebels suggested on Friday that clandestine Turkish nationalists may have assassinated three Kurdish activists in Paris, but Prime Minister Tayyip Erdogan said the killings appeared to have been the result of an internal feud. The Kurdistan Workers Party (PKK) said the execution-style killings in an institute in central Paris had been premeditated and planned and warned France would be held responsible if it failed to get to the bottom of their deaths. ...