The United States government said Thursday that nine Japanese auto-parts companies and two executives have pleaded guilty to price-fixing and will pay more than $740 million in fines. The parties, in separate conspiracies, fixed the prices of more than 30 different products sold to US car manufacturers and installed in cars sold in the United States and elsewhere, the Department of Justice said in a statement. The products include seatbelts, radiators, windshield wipers, air conditioning systems, power window motors and power steering parts. The Justice Department said that Hitachi Automotive Systems Ltd. had agreed to pay a $195 million fine, the largest among the penalties announced. The plea agreements require court approval. Mitsubishi Electric Corporation was hit with the second-largest fine, at $190 million. The other companies are Mitsubishi Heavy Industries, Jtekt Corp., Mitsuba Corp., NSK Ltd., T.RAD Co. Ltd., Valeo Japan Co. Ltd. and Yamashita Rubber Co. Ltd. The two executives are Tetsuya Kunida, a Japanese citizen and former executive of a US subsidiary of a Japan-based automotive anti-vibration rubber products supplier, and Gary Walker, a US citizen and former executive of a US subsidiary of a Japan-based automotive products supplier. The former employers of the two executives were not identified by the Justice Department. Each of the companies and executives has agreed to cooperate with the ongoing investigation, the department said. The cases involved parts sold to Chrysler, Ford and General Motors, and the US subsidiaries of Honda, Mazda, Mitsubishi, Nissan, Toyota and Subaru. The price-fixing conspiracies took place in a range from 2000 to 2012. \"These international price-fixing conspiracies affected more than $5 billion in automobile parts sold to US car manufacturers, and more than 25 million cars purchased by American consumers were affected by the illegal conduct,\" Attorney General Eric Holder said in the statement. The announcement was the latest crackdown in the Justice Department\'s long-running investigation of price-fixing and bid rigging in the US auto industry. Holder said that the Antitrust Division\'s auto-parts probe, the largest it has ever pursued in terms of scope and the commerce affected by the illegal trade, had uncovered more than a dozen separate conspiracies aimed at the US economy. \"As we have uncovered each auto part conspiracy, we have continued to find more and more parts that are involved. And our work isn\'t done. We will continue to check under every hood and kick every tire to make sure we put an end to this illegal and destructive conduct,\" Holder said at a news conference, according to prepared remarks. The department has coordinated its investigation with the European Union\'s executive arm, the European Commission, and competition authorities in Australia, Canada, Japan, Mexico and South Korea. Including the charges announced Thursday, a total of 20 companies and 21 executives have been charged in the ongoing investigation. All 20 companies have either pleaded guilty or have agreed to plead guilty and agreed to pay more than $1.6 billion in criminal fines, the department said.