Wait, in the article about his arrest there's the following quote:

When officers questioned him, he said he was being sought on a murder warrant.

So let me get this straight. You've fled to Arizona, you're sitting at the border to Mexico, and the border inspection people come up to you and ask why you're loitering around and you say "Oh, I'm being sought on a murder warrant."

Methinks that perhaps our friend Marcus isn't exactly the brightest crayon in the box.