The U.S. Department of Justice stepped into Kobe Steel Ltd.'s data-falsification scandal, as a new report claimed that the steelmaker's plants had been rigging product quality data for decades.

Kobe Steel said its U.S. subsidiary received on Oct. 16 a request from the Justice Department seeking documents related to compromised products sold to U.S. customers.

"The company and its subsidiaries will sincerely cooperate with the investigation," Kobe Steel said in a statement, adding that the scandal's potential impact on business performance is currently unclear.

Kobe Steel said Oct. 8 that some of its aluminum and copper products were found to be falsely labeled to show that they conformed to the specifications requested by customers. The company, which was investigating the issue, later admitted that about 500 companies had been affected by the compromised data.

The Nikkei Asian Review, citing a source knowledgeable about the situation, reported that systemic falsification of product quality data happened for decades at some Kobe Steel plants in Japan, surpassing the roughly 10-year time frame set by the company.

Airbus SE and Boeing Co. are among the companies reportedly investigating whether they used any of the materials affected by the falsified data, according to Kyodo News.