united states and around the world. world. you are in "the situation room." -- captions by vitac -- www.vitac.com fresh concerns for toyota, and especially for those who drive its vehicles. federal authorities here in the united states have now opened a formal investigation at the breaking problems into toyota's popular prius even as the carmaker steps up efforts to fix the gas pedal problem in a range of models. brian todd has been digging into the range of problems and jessica yellin owns a prius and she is looking at the braking problems that we are now talking about. jessica, tell our viewers here in the united states and around the world what is going on. >> wolf, i noticed this problem almost immediately when i bought the car last year. it was a sensitivity i felt when i was driving in certain parts of the road with my brakes. i have been trying to deal with toyota to resolve this since last year. it has been very frustrating.