I think the only defense here would be if the soldiers came up with some reasonable explanation of why they thought the vehicles were hostile. Its kind of hard to imagine, especially with shooting the follow up vehicles, but motive seems like the only unclear part where there is any potential for a defense.
One part that is really confusing, is if they knowingly intentionally targeted the ambulance because they thought they could get away with it if they destroyed the evidence, why leave witnesses alive? If you assume the motive was an intentional massacare with point blank executions, it doesn't entirely make logical sense to leave witnesses.
One part that is really confusing, is if they knowingly intentionally targeted the ambulance because they thought they could get away with it if they destroyed the evidence, why leave witnesses alive? If you assume the motive was an intentional massacare with point blank executions, it doesn't entirely make logical sense to leave witnesses.