A SHALLOW magnitude 6.6 earthquake has struck off the coast of eastern Taiwan at a depth of one kilometre, the US Geological Survey says.
The Pacific Tsunami Warning Centre did not issue a tsunami warning following the quake, but Japan's national broadcaster NHK said a tsunami as big as one metre was forecast to hit the Okinawa island chain.
NHK said waves were possible on several islands in the southern chain after a very shallow quake centred on Yonaguni in the south-west, near Taiwan.
"We are issuing warnings via the radio," Satoshi Shimoji of the Miyako City government told NHK.
"We want residents to get as far as possible from the sea," he said.