Hong Kong leads Asian shares lower as Beijing readies new security law

TOKYO (Reuters) - Hong Kong shares tumbled on Friday after Beijing moved to impose a new security law on the city after last year's pro-democracy unrest, risking fresh protests and further straining fast-deteriorating U.S.-China ties. Hong Kong's Hang Seng index fell 3.7% to a seven-week low, helping to pull down MSCI's broadest index of Asia-Pacific shares outside Japan 1.2%.Japan's Nikkei slipped 0.25%, while South Korea's Kospi fell 0.7%.China is set to impose new national security..