For more than 40 years the identity of the Zodiac killer has eluded police. Blamed for at least five murders in San Francisco between 1968 and 1969, he taunted detectives and their inability to catch him by sending letters and clues to the local newspaper. Now a former police officer says he has finally solved the mystery. In a new book Lyndon Lafferty says the killer is a 91-year-old alcoholic man living in northern California. The only catch: Mr Lafferty refuses to name his suspect. Mr Lafferty claims the killer is now a 91-year-old man living in Solano County but...