A Hong Kong police officer has been suspended from duty after he was arrested and charged with assaulting his girlfriend during an argument.The officer, 28, from Hong Kong Island regional headquarters was alleged to have assaulted his 29-year-old girlfriend in a flat on Hiu Kwong Street in Sau Mau Ping on the morning of August 18.A police spokesman said the pair had argued over relationship issues and the woman had been left with arm injuries after a tussle. She was later treated at United…