Yuan Zhen
After the end of the campaign against Lulong and Chengde rebels, Pei Du was recalled to Chang'an to serve as chancellor. Soon thereafter, there were allegations that Yuan Zhen (who had been made chancellor by this point as well) had plotted to assassinate Pei. Investigations did not yield positive evidence for the allegations, but as a result, both Pei and Yuan were removed from the chancellor posts.