HONG KONG -- Mounting public anger in Asia over soured investments in complex financial products tied to Lehman Brothers Holdings Inc. is fueling a public backlash and calls for tighter regulation.

In Hong Kong, more than 1,000 investors marched on the city's legislature Wednesday, saying they were conned into buying now-defunct Lehman Brothers derivatives called "minibonds" from local banks that pitched them as safe investments. Investors were left holding 12.6 billion Hong Kong dollars (US$1.62 billion) in Lehman minibonds,...