And speculation abounds. The story was written before 20 year-old Kevin Ward died of his injuries.
There is a link to that video in the first linked to story.The facts will come out soon. Anything earlier is speculation.
Having moved recently to North Carolina, I have witnessed some local track racing. There is one track in particular- Bowman Gray in Winston-Salem which has deteriorated to "wrestling on wheels". I have said recently that someone would get killed soon, due to tempers. I hope that what Tony Stewart did was not intentional, and I will pray for the other driver, Kevin Ward Jr.
NASCAR Driver Tony Stewart involved in serious incident at dirt track
From Yahoo Sports:
Tony Stewart struck and killed driver at New York dirt track