More than 17.8 million vehicles, child seats and vehicle equipment were recalled last year, said the U.S. federal auto regulatory agency on Thursday in a statement. Car manufacturers issued 664 safety recalls in 2012, slightly more than the previous year, said the U.S. National Highway Traffic Safety Administration (NHTSA) housed in the Department of Transportation. According to the NHTSA's report, about 586 of last year's recalls were related to vehicles for a total of 16.2 million autos, with slightly more than half made by Toyota and Honda. Toyota had 12 recalls covering 5.3 million vehicles, including Scion and Lexus. Honda and its Acura brand had 16 recalls affecting roughly 3.4 million vehicles. While some automakers described their recalls as voluntary, nearly 9.4 million of the total recalls resulted from the agency's investigations initiated by consumer complaints. In 2012 the auto regulator received 41,912 complaints concerning potential safety defects, compared with 49,417 in 2011. "Consumers are the lifeblood of the recall process and recalls are often the direct result of a government investigation into consumer complaints," said NHTSA Administrator David Strickland. The traffic safety watchdog has been requiring automakers to recall vehicles since 1966 and has announced over 518.7 million vehicles.