Washington, D.C. – The U.S. National Highway Traffic Safety Administration (NHTSA) will open a formal investigation into allegations of momentary loss of braking capability on uneven road surfaces, potholes or bumps in the 2010 Toyota Prius.

The Office of Defects Investigation said it has received 124 reports from consumers, including four reports alleging that crashes occurred. Investigators have spoken with consumers and conducted pre-investigatory field work.

“Safety is our top priority,” said Transportation Secretary Ray LaHood. “That is why in recent weeks NHTSA has also issued a consumer advisory on the recall of several models of Toyota vehicles and the Pontiac Vibe involving pedal entrapment and sticky accelerator pedals. We will continue to monitor these issues closely.”

In a statement, Toyota Canada said it is working with Transport Canada on the Prius brake issue, but said that “until our investigation is completed, it would be premature to comment.”

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