Aren't white suspects routinely mentioned? Its like Republican and Democrat. You know when a particular tag is missing from a story, its like the dog in the Arthur Conan Doyle story that didn't bark. And which is significant all on its own.
From what I have noticed, newspapers generally provide a physical description if the criminal is at-large - but not if he has already been arrested.
For example, in the same paper (NY Post), a rapist who had committed a series of rapes (and was still on the loose) was racially identified, along with his height, approximate weight, what he was wearing, etc.
That is to help us (the public) assist the police in their search.