Obama motorcade volunteer driver, 24, admits she had no training

There are between 20 and 30 cars that make up the official motorcade of the President of the United States - a security procession that travels, usually at high speeds and with green-light corridors, with the commander-in-chief everywhere he goes.

A 24-year-old California student has now revealed how she was selected as one of many volunteer drivers to be part of that chain of vehicles, 'following Obama all over San Francisco' for a day - despite having no experience, no training and, in what experts have called the most troubling, no idea what to do in an emergency.

Natalie Tyson even read a college textbook while waiting for the convoy to get back on the road, and posted pictures to her Facebook of the October experience, one of which was captioned: 'Me, wondering why anyone would trust me with a 15-passenger van full of reporters.'

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