then he moved on to quell disturbances along the Danube frontier. In Rome, Hadrian's former guardian and current Praetorian Prefect, Attianus, claimed to have uncovered a conspiracy involving Lusius Quietus and three others leading senators, Lucius Publilius Celsus, Aulus Cornelius Palma Frontonianus and Gaius Avidius Nigrinus. There was no public trial for the four – they were tried "in absentia", hunted down and killed. Hadrian claimed that Attianus had acted on his own initiative, and rewarded him with senatorial status and consular rank; then pensioned him off, no later than 120. Hadrian assured the senate that henceforth their ancient right to prosecute and judge their own would be respected.