These demons may have misunderstood the concept of a peacekeeping force. Perhaps they focused their understanding on the word "force" rather than "peacekeeping". Nevertheless, this was not important, because the term itself was just a cover used in Hao Ren's report.
After learning about the Council of Elders, Hao Ren knew that this incident had to be resolved by tough means.
After clearing away the last handful of guards inside the temple, the demon king's soldiers began to estimate the damage done and investigate the interior structure of the newly-captured ruins. Brutalus led the demons to set up a giant runestone device in the square to activate the Demonic Barrier and consolidate the place into a new stronghold. Looking at the thick smoke still lingering on the battlefield, Hao Ren turned and said, "Let's go and see… Oh my god, Lily, what's wrong with you?"