A day after US-based investment banker announced its intension to file for bankruptcy protection, three of its Asian subsidiaries suspended their operations.

"Lehman Brothers Asia Limited, Lehman Brothers Securities Asia Limited and Lehman Brothers Futures Asia Limited have suspended their operations with immediate effect, including ceasing to trade on the Hong Kong Securities Exchange and Hong Kong Futures Exchange, until further notice," Lehman Brothers Asia said in an email statement.

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The asset management company, Lehman Brothers Asset Management Limited will continue to operate on a business as usual basis, it said.

"A further notice concerning the retail structured products issued by and/or arranged by any Lehman Brothers group company will be issued as soon as possible," it added.

Investment banking major Lehman Brothers had filed for bankruptcy protection from its lenders, to whom it owes over $600 billion.

The investment bank, which has survived many a financial crisis over the past century, also said it is trying to sell some of its key businesses such as investment management and broker-dealer operations.

The filing for Chapter 11 bankruptcy protection, which allows a company to restructure while creditor claims are held at bay, was made in the US Bankruptcy Court in the Southern District of New York by the investment bank's holding company, Lehman Brothers Holdings Inc.

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