The man most likely to head the Hong Kong government for at least the next two years received backhanded, early congratulations yesterday - from a mysterious source. Two large banners were hung on railings near Chungking Mansions in Tsim Sha Tsui, proclaiming: 'We welcome Tsang Yam-kuen's stepping down as Team Clean's captain.' Chief Secretary Donald Tsang Yam-kuen was put in charge of the Team Clean taskforce, set up in May 2003, to conduct a clean-up of Hong Kong after the Sars outbreak. But nobody seems to know who put up the signs. A construction worker said: 'The banners were already there when I started my work nearby, at about eight o'clock.' Police said they had referred the case to the Food and Environmental Hygiene Department, which did not reply to questions about it. A spokeswoman for the Lands Department said they were trying to find out who erected the banners and whether they had permission to do so.