Holt's disappearance sparked "one of the largest search operations in Australian history", but no trace of his body was ever found. At 10 p.m. on 18 December, Governor-General Lord Casey announced he had terminated Holt's commission as prime minister upon his presumed death. A police report released in early 1968 made no definitive findings about Holt's death, while a coronial inquest in 2005 returned a verdict of accidental drowning. It is generally accepted that Holt overestimated his swimming ability. Some have alleged that Holt committed suicide, but those close to him rejected this as uncharacteristic of his personality. Conspiracy theories have included suggestions that Holt faked his own death, was assassinated by the CIA, or was collected by a submarine so that he could defect to China.