A magnitude-7.1
aftershock has rocked Japan on the one-month anniversary of a massive
earthquake that spawned the deadly tsunami.

A warning has been issued for a one metre tsunami, the
same as after another 7.1 aftershock that shook the northeast coast
last week. There was no tsunami after that quake.

 Shoppers at a large electronics store in central Sendai yelled and screamed in panic and they ran outside, though the shaking made it hard to move

Mothers grabbed their children, and windows shook. After a
minute or two, people returned to the store.

The United States Geological Survey reported said the
very shallow quake was centred 22km southwest of Iwaki, south of the
stricken Fukushima nuclear plant.

The Pacific Tsunami Centre said the quake had not
triggered a widespread tsunami that could reach the US and Canadian
West coasts but could cause a local one.

The operator of the crippled Fukushima Daiichi nuclear
complex said there were no irregularities at the plant following the

Tokyo Electric Power Co also said workers outdoors at the Fukushima Daiichi plant were evacuated after the quake.