April 7, 2011 Earthquake.

Powerful 7.4 aftershock hit Japan.

April 7, 2011 - Japan –Powerful aftershock 7.1 Magnitude earthquake hit the East Coast of Honshu Japan.

A major earthquake has shaken the northeast of Japan - prompting a tsunami warning for the coast devastated by last month's earthquake.

The warning issued after the 7.1 magnitude quake was subsequently lifted cancelled by the Japanese meterological agency.

No further damage was detected at the crippled Fukushima plant and workers were apparently evacuated without any injuries.

There were no immediate reports of damage elsewhere, although people in areas covered by the tsunami were urged to move to higher ground.

US Geological Survey said the aftershock struck 40 miles (66 km) east of the coastal city Sendai, at a shallow depth of 15.9 miles (25.6 km).

In the capital, Tokyo, buildings shook.

NHK public television cited police as saying seven people had been injured, two of them seriously.

The broadcaster also showed power was off in parts of Sendai, a regional commercial hub badly shaken last month's double disaster.

It comes as the country struggles to bring the Fukushima 1 plant under control after the quake and tsunami on March 11.

The disaster killed, or left missing, about 28,000 people.

Workers at the Fukushima plant have began pumping nitrogen, an inert gas, into a stricken reactor, with engineers concerned a build-up of hydrogen may cause an exploion.

The site suffered a series of blasts last month, with radiation leaks prompting widespread evacuation of residents in the surrounding area.