Question about No Country for Old Men (the book) -- Open Spoilers!

Rather than reopen any of the old threads (which I couldn’t find using the Search feature anyway – the words are apparently too short), here’s another NCFOM thread.

In the book, there’s some stuff toward the end that has me confused as all get out. Right after Carla Jean calls Ed Tom to tell him where Llewellyn is headed, there are a couple of paragraphs describing two Mexicans who are listening to something, I think on a radio – maybe they’re monitoring the police band.

One of them grabs a gun and takes off in a Barracuda.

Awhile later we read about a man hosing blood off a broken window, the window of a Barracuda.

Meanwhile, Ed Tom is on his way somewhere and passes a burning car – I think it’s a police vehicle – with some state troopers at the car. He doesn’t stop.

A bit later, Ed Tom talks about a Mexican being charged with killing someone, and Ed Tom thinks he’s innocent, but the guy is convicted. Ed Tom goes to see the guy in jail and the guy laughs at him, says yeah he killed the trooper and put him in a car and burned him up, “burned him to grease”, I think he says.

If he killed a trooper and set the police car on fire, why was he cleaning blood off the Barracuda’s window? Did he shoot the trooper through his car window? Why would Ed Tom think he was innocent? Did he think Anton did it?

Was the Mexican in the Barracuda one of the survivors of the shootout at the motel? If so, what did he hear that made him rush off with his gun? Or was this just another example of senseless violence?