The quake was the 7th worst in history, according to American agency, and also the worst on record in Japan
The quake triggered a tsunami that reached areas of the Japanese city of Sendai, on the island of Honshu, the main Japanese islands.
Cars and boats were swept away, and the images of destruction, made the helicopter, are impressive. A local TV showed video of the giant wave drag cars on his arrival to the coast.
In many places, the sea passed through protective levees and moved several miles by land, recalling scenes from the tsunami that occurred in the Indian Ocean in 2004.
Alert in Pacific
Alert in Pacific
The Tsunami Warning Center Pacific, U.S. agency issued a warning to many countries in the Atlantic Ocean coast, warning of the possibility of the arrival of waves of up to ten meters, but so far no reports of destruction outside of Japan
Several governments have issued warnings, and ordered the evacuation of some residents of coastal areas.
Learn more - Fukushima nuclear accident 
Radiation MonitoringOn March 28, deposition of iodine-131 was detected in 12 provinces, and deposition of cesium-137 in nine provinces.
The highest values were observed in Fukushima Prefecture, with 23,000 becquerels per square meter of iodine-131 and 790 becquerels per square meter of cesium-137.
In other provinces where the deposition of iodine-131 was measured, the range was from 1.8 to 280 becquerels per square meter. For cesium-137, the range was from 5.5 to 52 becquerels per square meter.
The limits for Japanese intake of drinking water for children are 100 becquerels per liter.
In Shinjyuku district of Tokyo, the daily deposition of both iodine-131 and cesium-137 was below 50 becquerels per square meter. No significant changes were reported in 45 provinces in the gamma dose rates compared to yesterday.
Since March 28, information on radioactivity in drinking water collected mainly in the Japanese Ministry of Health, Labour and Welfare indicate that recommendations for restrictions based on the concentration of I-131 remain in force only in four localities in Fukushima Prefecture. To date, there are no recommendations for restrictions that were based on Cs-137.
Five soil samples collected at distances between 500 and 1000 meters from the chimney of Units 1 and 2 nuclear power plant in Fukushima 21-22 March, were analyzed for plutonium-238 and the sum of plutonium-239 and plutonium- 240.
Plutonium-238 was detected in 2 of 5 samples, while the plutônio-239/240 was detected in all samples, as expected.
Concentrations reported for both plutonium-238 and plutônio-239/240 are similar to those filed in Japan, as a result of nuclear weapons tests in the past.
The relationship between concentrations of plutonium-238 and plutônio-239/240 in two of the samples indicate that small amounts of plutonium could have been released during the accident in Fukushima, but this must be better evaluated.
The highest values were observed in Fukushima Prefecture, with 23,000 becquerels per square meter of iodine-131 and 790 becquerels per square meter of cesium-137.
In other provinces where the deposition of iodine-131 was measured, the range was from 1.8 to 280 becquerels per square meter. For cesium-137, the range was from 5.5 to 52 becquerels per square meter.
The limits for Japanese intake of drinking water for children are 100 becquerels per liter.
In Shinjyuku district of Tokyo, the daily deposition of both iodine-131 and cesium-137 was below 50 becquerels per square meter. No significant changes were reported in 45 provinces in the gamma dose rates compared to yesterday.
Since March 28, information on radioactivity in drinking water collected mainly in the Japanese Ministry of Health, Labour and Welfare indicate that recommendations for restrictions based on the concentration of I-131 remain in force only in four localities in Fukushima Prefecture. To date, there are no recommendations for restrictions that were based on Cs-137.
Five soil samples collected at distances between 500 and 1000 meters from the chimney of Units 1 and 2 nuclear power plant in Fukushima 21-22 March, were analyzed for plutonium-238 and the sum of plutonium-239 and plutonium- 240.
Plutonium-238 was detected in 2 of 5 samples, while the plutônio-239/240 was detected in all samples, as expected.
Concentrations reported for both plutonium-238 and plutônio-239/240 are similar to those filed in Japan, as a result of nuclear weapons tests in the past.
The relationship between concentrations of plutonium-238 and plutônio-239/240 in two of the samples indicate that small amounts of plutonium could have been released during the accident in Fukushima, but this must be better evaluated.
