The Wall Street Journal on Wednesday attacked last week's filing of a class-action lawsuit in California by five Chinese nationals and four Chinese-Americans seeking compensation from two Japanese corporate groups they claim forced them into slavery during World War II.

"How is it possible to sue companies 55 years after the fact, in a court 5,000 miles from the event?" the paper said in an editorial.

The paper blamed the filing of the suit against the Mitsubishi and Mitsui groups of companies in a Los Angeles court on U.S. trial lawyers, "who have pushed through laws that allow them to profit from an ever wider circle of human misfortune."

In July last year, California became the first U.S. state to introduce a law allowing former prisoners of war held by Nazi Germany, Japan and their allies to bring damages suits against companies that used them as forced laborers.

Based on that law, some 30 lawsuits have been lodged in Californian courts by former POWs against Japanese companies.

"While the cases remind us that terrible things happen in war, they also demonstrate that justice can be turned on its head in peacetime, too," the Journal said.

The paper added that while Japan's wartime atrocities should not be forgotten, "blaming today's Japanese companies for these crimes that took place more than half a century ago defies credulity."