Details are emerging about the trains that were destroyed in the Japanese earthquake and tsunami, and what happened to them after they went missing. Overall, there is still a lack of information about some of the wilder rumours, but it has been confirmed that at least one wrecked train has been found, with all the passengers dead inside.
The train was near Nobiru Station on the Senseki Line, north of Sendai, when the earthquake happened. It appears that the train derailed at high speed. There is no clear indication of whether anyone survived the initial accident, but the train seems to have then been washed across the land by the subsequent tsunami. By the time it was found, everyone inside had died.
The Senseki Line runs from Aoba-dori Station in Sendai to the main station in Ishinomaki. During peak times there can be as many as 12 trains per hour on this line, but the earthquake struck in the mid-afternoon when there are usually 4 or 5 per hour.
There are still stories that as many as three other trains are unaccounted for. Unfortunately, information coming out of Japan is still fairly chaotic as the Japanese authorities struggle to deal with the scale of the disaster.
EDIT: It seems that the stories of destroyed trains were an urban legend that spread wildly in the immediate aftermath of the disaster. Read more here.