A

Johnson & Johnson

(JNJ) - Get Report

plant in Puerto Rico is being probed by the U.S. government after an anemia drug manufactured there was linked to growing incidence of a blood disease in Europe and Canada.

The criminal investigation by the

Food and Drug Administration

and

Justice Department

was prompted by an employee of the plant who claims in a lawsuit he was fired after protesting allegedly lax procedures there, the

New York Times

reported.

Johnson & Johnson confirmed the probe, saying it believes it pertains to record keeping, but said the allegations were false. It said even if they had merit they wouldn't have affected the drug's integrity.

The

Times

story says it's unclear whether the government suspects that manufacturing violations are responsible for the illnesses. A person close to the situation told the newspaper that the government became active only this spring as concern about the illnesses grew. A year earlier, the government had declined to intervene in the lawsuit

The factory manufactures Eprex, a drug that raises levels of red blood cells in people who are undergoing kidney dialysis or suffering from anemia caused by chemotherapy.

Health authorities in Europe and North America have become increasingly concerned over the last few months about a rise in the number of Eprex users who have developed pure red cell aplasia, a condition in which the body can lose its ability to produce red blood cells.