NHK on Thursday, quoting the results of measurement and survey made by the Ministry of National Land and Communications, said that ground sinking was observed in various places centering around the Pacific coasts of Tohoku region.

According to them, the area below 0 m sea level covered just 3 square km before the occurrence of the quake in some areas including Wakabayashi ward in Sendai City and Natori City of Miyagi Prefecture but it reached 16 square km or five times that after they were rocked by the quake.

A vast area below 0 m sea level hardly to be seen before was discovered in Iwanuma City and Watari chon of the above-said prefecture.

It was clarified that the area whose level was just the same as that of the surface of sea water during the high tide reached 56 square km at present or 24 square km larger than that before the occurrence of the quake.

It was reported that ground sank in areas of Natori and Iwanuma cities nearly 5 km from the coast.

Not only roads but buildings are submerged in the sunken areas in the period of flood and dead fishes seen floating at inundated houses.

Noting that inundation is occurring almost every day in the area extending 400 km on the northeast coast, sources said that it was miserable to see inhabitants in the afflicted area undergoing such disaster even before the aftermath of the quake is not fully eradicated.

Meanwhile, Tokyo Shimbun on Thursday released data about amounts of radioactive materials detected in various prefectures of Tohoku and Kanto regions for 16 hours till 9:00 a.m.

According to the data, amounts of radiation in Fukushima Prefecture reached 1.7 microsievert per hour and those in Tochigi Prefecture 0.67 microsievert per hour, the highest in the ordinary times.

In the meantime, the Ministry of Forestry and Fisheries clarified that radioactive substance higher than the legal level was detected in feed for domestic animals in Chiba Prefecture.