If they were saved, someone must have shared with them the words of the Bible, the gospel of Jesus Christ. And they believed the words that were shared. Faith come by hearing and hearing by the words of God.
However, this does not address the fact that there are people out there that have heard about Jesus, Maybe has been preached to yet have not accepted Jesus up to this point. At that point just prior to Death, if they call HIS name, I believe they will be saved.
It is said that more lives (men) were saved in a fox hole (WWII) more that any other place history up to this point in time. This has changed over the years but these young fellows had a lot of opportunity to get saved prior, yet find themselves in a FOX HOLE waiting for the hammer to drop finally made them make a choice. There are a lot of people that are like these soldiers and some of them will never get that chance to call His NAME...WHY Wait?
Have a Blessed Day
Blade