HONG KONG -- A political mystery arose in Shanghai as the year drew to an end. Few foreigners took much notice. Yet the unexplained incident could indicate that a bumpy year lies ahead for politics in China.

The mystery arises over the effective sacking of the highly regarded mayor of Shanghai, Xu Kuangdi, who since 1995 has been in the forefront of organizing Shanghai's extremely rapid growth.

Xu had been on a trip to Europe, trying to gain acceptance for Shanghai as the host city to a World Expo in 2010. No sooner had he arrived back from Paris, and he was shanghaied by an abrupt announcement.