As early as 2000, the Japanese auto supplier Takata manipulated test results on airbag inflaters, according to a person with direct knowledge of internal company documents.

The data manipulation, whose details were first reported by The Wall Street Journal, involved tests intended to demonstrate compliance with automakers’ design specifications, said the person, who was not authorized to speak.

Eight deaths and over 100 injuries have been linked to defective airbags made by Takata, one of the world’s largest airbag makers. The bags’ inflaters can rupture, propelling shrapnel into the passenger compartment. More than 19 million vehicles in the United States, and millions more worldwide, have been recalled.

This month, Honda dropped Takata as a supplier of certain inflaters, saying that Takata had “misrepresented and manipulated test data.” Honda has so far declined to give details but has said that it is aware of “apparent instances of misleading or inaccurate data that were provided to Honda over time” related to “a variety of testing.”