NEW YORK (CNNMoney.com) -- Federal safety regulators said Wednesday they have received 10 complaints from drivers alleging sudden acceleration in Toyota vehicles that have already been repaired under the automaker's recent recall.
The National Highway Traffic Safety Administration said it has reached out to the consumers in question to gather more information about the complaints, which were not immediately verifiable.
"NHTSA has already started contacting consumers about these complaints to get to the bottom of the problem and to make sure Toyota is doing everything possible to make its vehicles safe," David Strickland, NHTSA's administrator, said in a prepared statement.
"If Toyota owners are still experiencing sudden acceleration incidents after taking their cars to the dealership, we want to know about it," he added.
Cindy Knight, a Toyota spokeswoman, said the company is aware of the post-repair complaints and has asked NHTSA to help Toyota contact the customers in question.
"We are confident that our Toyota vehicles are safe, and we're doing everything we can to ensure our customers are satisfied with the repairs we've been making," Knight said. "We have rigorously tested those solutions the Toyota engineers have developed and we're very aggressively investigating any complaints."
Toyota has recalled more than 8 million vehicles worldwide for problems related to sudden acceleration, which have been blamed for several accidents resulting in injuries and death. The automaker has repeatedly apologized for the lapses in quality control, and Toyota technicians are working extended hours to repair the recalled vehicles.
In testimony before the U.S. Senate Tuesday, Toyota executives said the automaker has already serviced about 1 million of the recalled vehicles.
The sudden acceleration issue has been in the spotlight since it was disclosed last month that an accident involving a Toyota vehicle killed four people in San Diego last August.
That accident sparked the recall of millions of Toyota vehicles for problems with floor mats that could cause accelerator pedals to become trapped. Toyota has subsequently recalled millions more cars for "sticky" accelerator pedals.
Since 2000, NHTSA has identified a total of 43 complaints of fatal incidents that allegedly involved sudden acceleration in Toyota vehicles. While those complaints have not yet been confirmed, the reported incidents led to 52 fatalities and 38 injuries, NHTSA said.
Toyota has come under increasing pressure from Washington, with executives going before Congress in three separate hearings over the last two weeks.
Rep. Bruce Braley, D-Iowa, said he is "deeply concerned" about the possibility that repaired Toyota vehicles may still be prone to sudden acceleration.
"If these reports prove to be true, it is completely unacceptable that America's families are once again being put at risk," Braley said in a statement.
In a letter to Transportation Secretary Ray LaHood, the congressman said the complaints highlight the need for a "thorough and credible investigations" into Toyota's safety record. He also questioned the effectiveness of recalls in ensuring the safety of the American public.
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