Ending dialog in “The Bridge on the River Kwai”

Question

In the war movie, The Bridge on the River Kwai (1957), at the end Major Warden has a brief dialog with the women porters.

The women back away from him as he exclaims:

I had to do it. They might have been captured alive. It was the only thing to do!

I don't understand this part of the film. At least it did not appear that he was trying to fire the weapon at the commandos (Shears and Joyce). In fact the only time an explosion occurs near them is after they are dead and a explosion lands near Colonel Nicholson.

Answer 1

However, if you watch it again, he did not know they were dead. His dialog about them being captured alive was the give away.

The scenes where they were instructing the younger commando that he would need to be able to kill gives up a bit of this. He was able to kill Saito but not the Colonel. Each of the commandos needed to have the ability to kill in close quarters.

And killing the Colonel was required to save the mission.

He was apologizing to the two women who loved those men hat died. he just wasn't aware when he fired they were dead.