<br/>A 6.9 magnitude earthquake hit off Japan's southern coast early today, shaking Okinawa and nearby islands. Japan's Meteorological Agency said a tsunami warning has been issued. The quake occurred off the coast of the island of Okinawa at a depth of 10 kilometres around two this morning, Indian Standard Time. It predicted a tsunami up to two metres near the Okinawan coast. There were no immediate reports of major damage or casualties. <br/><br/>Japan is one of the world's most earthquake-prone countries. In 1995, a magnitude-7.2 quake in the western port city of Kobe killed 6,400 people.