Now, here's a press release from Hong Kong Observatory:
A minor earth tremor was recorded by the Hong Kong Observatory at 7:53 p.m. today (Thursday, 14 September 2006).Three point five? Shake and shudder.
A number of local residents from various part of the territory reported to have felt this tremor, the duration of which was a few seconds. According to these reports, the intensity of the tremor was estimated to be iv (four) on the modified Mercalli Scale of xii (twelve).
Preliminary analysis placed the epicentre of this earth tremor over the sea near Dangan Island, about 36 kilometres south-southeast of Hong Kong. The magnitude was estimated to be 3.5 on the Richter Scale.