The following information comes from a letter in the Alexandria Gazette, a Virginia newspaper, in 1868.
An incident occurred on the farm of one Silas Brown (pseudonym). This worthy lived in Prince William Forest near Independence Hill (Virginia). He saw a creature a number of times near his barn and on one occasion was actually assaulted by it. The beast was described as being as large as a man, its back was 6'-8', its arms were substantial, it had large horns and awful claws which could be contracted into hoof-like structures. Its normal color was blue, but upon being angered it turned white. Another witness also claimed to have seen it.
If all of this is true, the assault on Brown does not seem to have been fatal and he does not seem to have thought it necessary to vacate his premises to avoid the creature, which might imply that the injuries he received were not too serious.