Japan escapes quake alarm damage

A strong earthquake has shaken northern Japan causing small tidal changes on its Pacific coastline but no damage or injury.

Several towns issued evacuation orders or advisories to residents nearest the coast but they were lifted about an hour and half later.

The Japan Meteorological Agency said the tremor was 6.8 magnitude. An aftershock of magnitude 5.9 struck followed about two hours later.

The town of Otsuchi in Iwate prefecture, where more than 800 died in last year's tsunami, issued an evacuation order to all households along the coast as a precaution.

Iwate was heavily damaged by last year's earthquake and tsunami. Thousands of aftershocks have shaken the region since then, nearly all of them of minor or moderate strength.

The magnitude 9.0 earthquake and tsunami on March 11, 2011 left 19,000 people dead or missing.

Japan marked the first anniversary of the disasters on Sunday, as the country still struggles to rebuild.

The latest tremor was centred about 150 miles south of Kushiro, Japan, on Hokkaido island. It was a relatively shallow six miles below the sea surface.

The quake was not felt in Tokyo, and there was no threat of a Pacific-wide tsunami.