Your first sentence assumes we know the assassins' motives. I question that.
Your second sentence assumes that any assassinations would be publicly known (eg assassination of a public figure). Assassination of non-public figures may well be impactful and yet go largely unheeded.
Your second sentence assumes that any assassinations would be publicly known (eg assassination of a public figure). Assassination of non-public figures may well be impactful and yet go largely unheeded.