It’s got nothing to do with Seattle—it is 150 miles east.
http://www.musicinelsol.com/MIESDrivingDirections.pdf
150 miles isn’t that far when you consider that illegals would have had to travel 2,300 miles just to get to Seattle. I’m not saying it’s definately illegals but I think it is a possibility.( I do know that if they were white, it would have appeared prominently in the story)