6.8 on the Richter

·At least five killed and 400 injured  · Quake sparks fire at nuclear plant

At least five people died and more than 400 others were injured when a powerful earthquake struck the north-west coast of Japan this morning, sparking a blaze at the world's biggest nuclear power station and flattening dozens of buildings. 

The quake, which measured 6.8 on the Richter scale, rocked towns in Niigata prefecture on the Japan Sea coast at 10.13am, triggering a tsunami warning that was later lifted, reports said.