Do you think this conforms with the principles set out in Buddhism

Please discuss the following prompt: There is a story of a Buddhist monk who was on a ship with a maniac who was killing everyone on board. The monk eventually decided to kill the man in order to prevent further harm of others on board. Do you think this conforms with the principles set out in Buddhism? Why or why not? How do you think karma and compassion come into play in this story?

2 pages long and please in Chicago style