A derailed train is seen in the quake-hit and tsunami-hit Miyagi Prefecture, Japan, on March 12, 2011. Over 5,000 people have been killed after?a?9.0-magnitude earthquake and ensuing huge tsunami hit northeast Japan.

A Japanese worker remained missing after saving 20 Chinese research students from the deadly earthquake and tsunami that killed?over 5,000 people.

When the tsunami hit Miyagi Prefecture on March 11, Sato Mitsuru, a commissioner with the Sato Fisheries Corporation,?led the Chinese research students to a safe place and went back to search for his wife and daughter. However, waves soon engulfed the area and Sato went missing.

Yi Yanan, a research student from?northeast China, said she saw Sato climb to a roof to avoid the tsunami, but he was quickly carried away by the water.

Sato's wife and daughter remained missing too.

Cao Jing, another?Chinese research student, said the executives of his corporation found a hotel for five Chinese students, even when they were out of touch with their own children.

Later, the five students were sent to a shelter and were united with other Chinese.

"I dare not imagine what would have happened if they hadn't helped us," Cao said.

Onagawa-cho had a population of 10,000, half of whom have not been found. All of the about 100 Chinese students were safe in the disaster. Many survived due to the help from locals.

(Xinhua and Global Times contributed the story.)