を殺害した

murdered

→ を
phrase Rare #36,828
murdered 殺害する is a formal term meaning “to murder” or “to kill.” The を marks the person who was killed, and した makes the verb past tense. The phrase usually appears after the victim’s name or other noun.
JA: 犯人は男性を殺害した。
EN: The criminal murdered a man.

トム教室にいた全員を殺害した

Tom killed everyone in the classroom.

囚人は警官を殺害したことを否定した

The prisoner denied killing the police officer.

警察は少女を殺害した男を逮捕した

The police arrested the man who murdered the girl.