The company said in an announcement that the problem had grown to include 8,374 metric tons of steel wire and special steel. Previously it said employees had quality data on certain copper and aluminum products and iron powder. 

The company said it has hired an outside law firm to investigate. The scandal, which broke at the beginning of the week, has caused shares to fall by more than 40%, wiping out about $1.8 billion in market value, according to 

The company previously said about 200 customers had been affected by falsified quality data. But during a press conference today, Kobe chairman and chief executive Hiroya Kawasaki, said the total number is around 500. 

He said it is unclear how many more cases will emerge, The Japan Times reported. 

“We are investigating all our business sections…as we were told by the industry ministry, we’d like to complete the investigation as soon as possible,” Kawasaki said, according to the newspaper.