Joe thinks chess is an evil game and creates a killer robot tasked with killing the greatest chess player on earth, whoever it might be. The robot succeeds with the task. Joe is clearly a murderer, not merely an attempted murderer. But suppose Joe is the greatest chess player on earth, though he had no suspicion of this fact. Then Joe has committed suicide. And is a murderer. Hence a suicide can be a kind of murder.
(I actually think suicide is generally murder. But that's a stronger claim.)