MELBOURNE - An Islamic State sympathiser planned to buy a gun and kill as many revellers as possible on New Year's Eve in Melbourne's popular Federation Square, police alleged Tuesday after foiling the plot. The 20-year-old, born in Australia to Somali parents, was detained in a raid on a house in the Melbourne suburb of Werribee on Monday. He is expected to be charged later Tuesday. Police claim he accessed a guide book online produced by Al-Qaeda on how to commit terror acts and use firearms, but was arrested before he could purchase an automatic rifle.