Tokyo, Mar 20 (IANS): An earthquake measuring 7.2 on the Richter scale struck north-eastern Japan on Saturday, prompting authorities to issue a tsunami warning for Miyagi prefecture.

The Japan Meteorological Agency warned of up to a 1-metre high tsunami in Miyagi and the first tsunami wave has already swept ashore in the city of Ishinomaki, dpa news agency quoted the national broadcaster NHK as saying.

The warning prompted some residents in Miyagi to rush to higher ground ahead of the possible arrival of tsunami, NHK footage showed.

There were no immediate reports of casualties or damage to property.

The quake also shook buildings in Tokyo.

The temblor occurred at 6.09 p.m. (local time), with its epicentre located at a latitude of 38.4 degrees north and a longitude of 141.7 degrees east, and at the depth of 60 km, the agency said.

On March 11, Japan marked the 10th anniversary of a magnitude-9.0 quake and resulting tsunami that struck the same region in 2011, leaving about 18,400 dead or missing.

The twin natural disasters caused a triple meltdown at the Fukushima Daiichi Nuclear Power Station, which spewed radioactive substances into the environment.

The nuclear emergency prompted hundreds of thousands of residents to flee their homes.

A month ago, a magnitude-7.3 quake also rocked the north-east, killing one person and injuring about 190 others.

Japan sits at the convergence of four tectonic plates, making it especially prone to seismic activity.

The country is also home to 100 active volcanoes.