Japan issued a tsunami advisory on Tuesday morning following a 6.9-magnitude earthquake in northern Japan, the meteorological agency said. The agency said a tsunami of up to one metre (3.3 feet) was forecast to hit the coast of Iwate at around 8:30 am (2330 GMT Monday).An evacuation warning was issued for coastal towns in Iwate prefecture in northeastern Japan on Tuesday after a tsunami warning was broadcast following a 6.9 magnitude earthquake.