Dramatic Testimony On Day One Of Tsarnaev Trial

A woman who lost her left leg after the first bomb went off at the 2013 Boston Marathon says she believed that was going to be the day she died.

Rebekah Gregory testified that she went to the marathon with her 5-year-old son, her boyfriend and his family to see his mother run. She says she remembers being hoisted into the air and thrown back by the strength of the bomb.

Gregory says she had 17 surgeries on her leg before deciding to have it amputated. That surgery was performed in November 2014.

Her testimony came on the first day of the trial of Dzhokhar Tsarnaev. His attorney today conceded in opening statements that Tsarnaev did, in fact, take part in the bombing. But she said it was because he was influenced by his older brother.