By Sumeet Chatterjee HONG KONG (Reuters) - Hong Kong's financial regulator has banned former Goldman Sachs banker Tim Leissner from re-entering the industry for life for his crimes linked to the multi-billion-dollar scandal at the Malaysian state investment fund 1MDB. The sanction is latest for Leissner who has already been barred from the banking sector in the United States and Singapore for his links to the scandal. Goldman itself is being probed by the U.S. Justice Department for its role as underwriter and arranger for $6.5 billion worth of 1MDB bonds. Apart from Leissner, another former Goldman banker Roger Ng and Malaysian financier Low Taek Jho have been charged in the United States for links to the alleged theft of billions of dollars from the Malaysian sovereign wealth fund. An estimated $4.5 billion was misappropriated from 1MDB by high-level officials of the fund and their associates between 2009 and 2014, the U.S. Justice Department has alleged.