Maimonides — "As for Gentiles with whom we are not at war… their death must not be caused, but…"
As for Gentiles with whom we are not at war… their death must not be caused, but it is forbidden to save them if they are at the point of death; if, for example, one of them is seen falling into the sea, he should not be rescued, for it is written: 'neither shalt thou stand against the blood of thy fellow'–but [a Gentile] is not thy fellow.