just in, we have learned that the federal bureau of investigation has opened a domestic terror investigation into the el paso shooting this morning that left 20 people dead and another 26 wounded. police so far have identified the alleged shooter as a 21-year-old white male from allen, texas, which is just north of dallas. he was arrested at the scene. the police chief also saying that the shooting has a nexus to a potential hate crime. citing a manifesto that they have obtained that may be connected to the alleged gunman. they say they're still working to confirm that it does belong to the shooter. i want to dive into this a little bit more with our chief media correspondent brian stelter. brian, we are getting a lot more information about this document. it's four pages long. it's entitled "i'm probably going to die today." he did not die. he was arrested peacefully without shots fired. what else was in this document that as we were saying we have not confirmed yet is actually connected to the shooter? >> right, that is correct.