7.1 Magnitude Quake Shuts Down 2 Japanese Nuclear Plants

Tsunami warning triggered but harmless wave reaches shore.

TOKYO April 7, 2011— -- A huge earthquake has again rattled northeast Japan shutting down two more nuclear power plants, and triggering a tsunami warning in the same region devastated in last month's quake.

Two power plants are reportedly off line following the 7.1 magnitude earthquake that struck coastal Miyagi Prefecture at 11:32 p.m. local time Thursday. The quake is the largest aftershock since the 9.0 quake struck the Northeast city of Sendai on March 11.

Thursday's quake was 25 miles deep.

People near the coast were told to immediately evacuate to higher ground, according to the Japanese meteorological agency. A small wave reached the coast around 12:40 a.m. Friday and the warning was lifted.

Buildings as far away as Tokyo, nearly 200 miles from Miyagi, trembled for about a minute.

In Ichinoseki, an inland city, buildings shook violently and items were knocked from shelves but there was no heavy damage reported.

Two plants in Oginawa and in Aomori Prefecture were knocked out in the latest tremor, but authorities said there was no threat of a radiation leak similar to that at the Fukushima plant.

The nuclear power plant in the fishing town Oginawa went offline following the aftershock. The plant served as a surprising ad hoc shelter in the wake of the March 11 quake but, authorities said, the reactor was intact.

The plant in Aomori is currently being cooled by an backup diesel generator, powering pumps to keep fuel rods there cool. All the rods are reportedly still fully submerged in a cooling pool.

The Tokyo Electric Power Company said there were "no anomalies detected" at the damaged Fukushima Daiichi plant, still on the verge of meltdown following March's historic 9.0 quake. All the workers at the Fukushima nuclear complex were evacuated today.

No elevated radiation levels were detected at the plant.

Service on many of the bullet train lines in the region has been suspended. No injuries have been reported.