The Nation (one of Bangkok's 2 English newspapers) thinks it was a professional hit, and set up by an unnamed journalist:

A replay of the incident pointed to the possibility of a set-up. Khattiya was giving an interview. The video camera of a reporter started to roll and the light from the camera beamed on his face. Within that second, Thomas Fuller, a correspondent of the New York Times who was about a metre away from the general, heard a loud noise like a firecracker lighting up the sky.

In his report for the New York Times' Thursday edition, headlined "Thai General Shot; Army Moves to Face Protesters", Fuller wrote: "The reporter, who was two feet away and facing the general, heard a loud bang similar to that of a firecracker.

"The general fell to the ground, his eyes wide open, and protesters took his apparently lifeless body to a hospital, screaming his nickname: "Seh Daeng has been shot! Seh Daeng has been shot!"

The loud bang that Fuller heard possibly came from a firecracker - not the gunshot from the Winchester .308 rifle, which was equipped with a silencer. The sniper fired his shot within the second when he could see Seh Daeng clearly with the help of the light from the video camera.

So then, who was the second journalist operating the video? In Fuller's account, he says that he was the only journalist remaining with Seh Daeng. Something doesn't jibe here. Was Fuller also operating the video?

Political observers said there are several theories behind the assassination attempt on Khattiya.

First, he could have been a target of revenge from a military regiment called Phayak Burapha, which lost the battle badly on April 10 against the red shirts. In that battle, the Phyak Burapha lost Colonel Romkhlao Thuwatham.

Second, hardcore elements of the red shirts wanted to strike down Khattiya so that the ensuing upheaval would go out of control and in the end a national government could be formed as a compromise.

Third, the military or the government in power wanted to eliminate him to dilute the hardcore element within the red-shirt movement.

My money is on door number 1, the revenge for loss of face motive. It's the most emotionally powerful and least complicated explanation--you diss me, I kill you in a way that shows I'm more clever and powerful than you are. Which is why it seems right to me.

Meanwhile, as of this morning (Saturday) the Bangkok Post reports that 16 people have been killed, 157 injured. They've got great pictures up on their site. For me it's shocking to see images like this one, in which a downtown overpass in a modern Asian city I know so well is turned into an urban warfare zone.

UPDATE: Under other circumstances, I might find the humor in the bad English translation. This is one of the signs the Army is putting up around the "militarized" zones (It's from a Thai photog's Twitter feed:

This one's from another Thai photographer on Twitter. The billboard slogan asks, in Thai, "When was your last holiday?":