A home-made bomb was yesterday thrown inside a Causeway Bay shop owned by a 'silent witness' from the trial of tycoon Albert Yeung Sau-shing. A Molotov cocktail was tossed inside Michael Lam Yih-jiun's fashion wholesale outlet on the 15th floor of the In Square after 11am. It did not explode. Mr Lam went to the shop to help police. An employee told detectives that a man looking for Mr Lam on Saturday had threatened to hurt her if he could not contact him. Mr Lam narrowly escaped jail for contempt of court in 1996 after he repeatedly answered questions with the phrase: 'I can't remember'. Mr Lam said he had lost his memory at the trial of Mr Yeung on charges of criminal intimidation and false imprisonment in May 1995.