The Japan Coast Guard was continuing to search on Monday for a chief officer who fell from a Pacific International Lines (PIL) containership.
The coastguard reported the 35-year-old Chinese national had been lost overboard from the 4,250-twu Kota Lazim (built 2008) on Saturday, 750 km east of Cape Nosabu in Nemuro.
The vessel had notified the organisation by email, the Goo website reported.
The coastguard sent an aircraft from Chitose airbase to search the area, as well as a patrol boat from Shiogama City.
This vessel was not expected to reach the site until Tuesday, however.
The PIL ship had a crew of 20. It was carrying cargo from Shanghai in China to Mexico.
The Singapore company has been contacted for further information.
Last week, the shipowner's legendary founder Chang Yung Chung (YC Chang) died aged 102.
His family said that he died peacefully in his sleep.
Chang incorporated PIL in 1967 as a shipowner and operator in the coastal trades.
Alphaliner now ranks PIL as the 10th largest container line by total capacity. It controls more than 100 vessels, of which 61 are owned and 46 are chartered.
