Senior staff of Maria's Bakery told all 400 employees late last night they were not needed at work this morning, as all outlets would be closed from today. The staff were informed individually by their supervisors by telephone after 9 pm. The supervisors were directed to hand in their keys. Maria's founder and owner, Maria Lee Tsang Chiu-kwan, 70, better known as the Queen of Cakes, could not be contacted at her Kadoorie Avenue home early today. Her maid said she was asleep. The closure of Maria's will leave thousands of people wanting to redeem pre-paid vouchers distributed by couples ahead of their weddings. Mrs Lee opened her first cake shop on December 11, 1966, and her business prospered into more than 100 outlets in Hong Kong, Taiwan, in Canada and the US. Close friends said last night that her health had deteriorated in recent years and she had handed operation of her businesses to a relative. The sudden closure of the bakery chain was disclosed by the Hong Kong Confederation of Trade Unions, which issued a brief press statement. General secretary Lee Cheuk-yan said he did not understand why the company should adopt such a 'sneaky method' to announce its closure. The first inkling there was trouble came with the instruction to supervisors to bring their keys to the company's head office at Yuk Yat Street in To Kwa Wan. Soon afterwards the supervisors began telling staff not to come to work this morning. At the head office on the ninth floor of Fuk Shing Industrial Building in To Kwa Wan, overnight staff were told at 10 pm to go home as the company would be ceasing business. Mr Lee said allowances and overtime pay for last month, amounting to more than $400,000, had not yet been paid. 'Nor have they got this month's salary,' Mr Lee said. 'We don't know too much about the closure and we have already set up a hotline - 2770-8668 - for Maria's employees to contact us,' Mr Lee said. In May 1984 when there were unfounded rumours that Maria's was in financial difficulties, customers jammed the chain's 47 outlets, leaving with armfuls of cakes. In November last year thousands of customers besieged St Honore Cake Shop outlets desperate to claim boxes of cakes with vouchers after rumours that the company was in trouble. At that time, Mrs Lee called on her experience in 1984 to tell the South China Morning Post that the best thing to do was to tell the public that all vouchers would be honoured.