From a quick Google search:
One story is particularly poignant. Daina Bradley lost a leg in the April 19 blast, and her mother and two children were killed. She recalls looking out the plate-glass window of the Social Security office a few minutes before the explosion and seeing a yellow Ryder pull into the driveway. That is where the terrorists left the truck. According to Bradley, it was there for three to five minutes. Then she saw a side view of an olive-skinned white man leaving the passenger side of the Ryder truck. He was wearing a dark blue jacket and a baseball cap. She does not believe that person, who left the truck and walked quickly away from the federal building, was McVeigh. After that, all she recalled was electricity running through her body and a sensation of falling into rocks. Prosecutors contend that Bradley is a trauma victim and therefore her account is not reliable.
Emphasis mine
Link to Gerald Oosners page
Link