Japanese shipping firm Mitsui O.S.K. Lines Ltd has paid about $39 million to a Chinese court towards securing the release of one of its ships which was seized over an alleged payments dispute dating back to World War II, Japanese media reported Thursday.

The Yomiuri newspaper and public broadcaster NHK, quoting unnamed people they said were familiar with the matter, said Mitsui had paid about 4 billion yen in compensation and interest to the Chinese court. Its ship, the "Baosteel Emotion" 226,434 deadweight-ton ore carrier, was seized on Saturday.

Mitsui O.S.K. spokesman Atsushi Seki said he could not immediately confirm the reports. He said the company was still working to release the vessel, which the Chinese court seized over Mitsui's alleged failure to pay compensation stemming from a wartime contractual obligation.

A number of court cases demanding compensation for forced wartime labour have arisen in China and South Korea. In February, two Japanese firms were sued in what media said at the time was the first instance where a Chinese court had accepted such a case.