Perseus had arranged for the assassination of Eumenes to take place during the latter's visit to Delphi, but the attempt failed. Gaius Valerius Valerius, who had been sent to investigate the situation in Greece and monitor Perseus, returned to Rome and agreed with the allegations Eumenes had brought to the senate. He also bought a woman who was involved in the failed plot and a Roman who claimed that Perseus had tried to coerce him into poisoning ambassadors to Rome. This intensified old enmities and led to Perseus being declared a public enemy, the Senate electing to wage war and the dispatch of an army to Apollonia on the western coast of Greece to occupy the coastal cities. The war was, however, put off for the year. Eumenes also prepared for war.