Tokyo: A series of earthquakes rocked North-western Japan within minutes of each other today (Oct 23, 2004) leaving four persons dead and more than 300 others injured besides destroying houses, cutting off power and derailing a bullet train.

The first quake measuring 6.8 on the Richter scale was centred near Ojiya city in Niigata State, about 256 kms north of Tokyo, the Japan Meteorological Agency said.

The quake was followed by nearly four more, including a magnitude 6.2 and 5.9 quake, the Agency said adding strong aftershocks were continuing.

Local authorities said one person died at a hospital after breaking his neck and around 60 people were injured in Ojiya and Kawaguchi in the State, 'Kyodo' News Agency reported.

In the city of Tokamachi, a man in his 30s was killed when a restaurant wall fell on him while a 65 year-old man died of shock, police said adding around 60 people were reported injured. A fourth death was reported but no details were available.

Around 60 people were also injured in Nagaoka and some 40 in Kariwa.

Prime Minister Junichiro Koizumi ordered a task force established in the crisis management centre at his office to help in relief and rescue efforts.

The powerful quakes left a trail of destruction with many houses toppled, some set afire and disruption of essential services. Power blackouts were reported at 250,000 households in large areas in Niigata State.

The Ojiya city Government said two people were buried by landslides in the city, while the Niigata State Government said 1,000 people left their homes and are staying at local shelters.

Several houses were destroyed in Ojiya, and eight cases of fire were reported in Nagaoka. Seven were extinguished.

The strong tremors were also felt in Tokyo and its surrounding areas.

Police said part of the Kanetsu, Hokuriku, Nihonkai-Tohoku, Banetsu and Joshinestsu expressways have been closed following the quake.

The quake also caused a Shinkansen bullet train on the Joetsu Line with 150 passengers to jump the tracks between Urasa and Nagaoka in Niigata State, East Japan Railway Co. said, adding there were no injuries.

Local authorities said the earthquake was so strong that building swayed several times. Most of the people were injured by objects falling from the impact of the quake.

The Agency said aftershocks are continuing in the area, and called for caution over possible strong intensity quakes.

Tokyo Electric Power Co. said its nuclear power plant in Kashiwazaki, Niigata State, is unaffected and running normally.