'Hellburner'--looking for a sci-fi story that contained that term

Question

I read a story--the first part of one, at any rate--years ago, and haven't tracked it down since. It started with a man been sent to a planet under attack to pose as a monk--he arrived in the middle of an assault, but still had to do penance for being late. So he wore a hair shirt, that created an agonising reaction. He was captured by the attackers (who took him for the man he was posing as), who then stood off the planet in their starships and watched as a 'hell burner' weapon tumbled out of deep space and torched the planet. The attackers then explained that they weren't responsible for the hell burner, but every time they arrived at a planet, a hell burner turned up afterwards, at shorter and shorter intervals.

As the story developed, there was some kind of time travelling dimension, and a character turned out to have his organs reversed. I may have got some details wrong, but this was the shape of it.

Anyone know this story, and the author?

Answer 1

This is "Patterns of Chaos" by Colin Kapp.

The voices emanate from a distant team of three monitors of the Special Assignments Group of the Federation, three monitors who see everything Bron sees, and hear everything he hears. The monitors are able to carry out sub-vocal conversations with Bron; from these exchanges, Bron gradually discovers that he is the most highly trained secret agent in the Federation’s Stellar Commando unit. His mission: pose as Ander Haltern, a philosopher and theoretician of marked genius, and the leader of a religious cult on Onaris.

...

However, while aboard the Destroyer flagship, Bron joins its crew in witnessing a catastrophic event: a ‘hellburner’ nuclear missile strikes Onaris, and incinerates the entire surface of the planet....... and its population of 200 million. Initially, Bron accuses the Destroyers of the atrocity. But when Cana, leader of the Destroyers, invites Bron to analyze the missile’s trajectory, Bron comes to a startling conclusion. The hellburner didn’t originate from any Destroyer ship…..but was launched from the distant Andromeda galaxy, 700 million years ago.