Recovered footage from a deceased Ukrainian Soldier that was released through official Russian channels captures the moment Russians crest the top of a hill and are challenged by the Ukrainian.

Challenge and Pass is a super old system that was specifically designed for situations like this. Every civilian who's seen the movie Saving Private Ryan knows exactly what the Challenge and Pass system is. It's a simple solution to a complex problem that often presents itself in conflict situations. Soldier A throws out the challenge word, and Soldier B has to immediately throw out the pass word. If Soldier B does not immediately yell out the pass word, Soldier A should assume that Soldier B is the enemy and open fire on him.

Relying on IFF signals such as armbands and lighting is not fool-proof, and this video is evidence of that. It was released today through official Russian sources, and it was recorded by a Ukrainian Soldier. As the Russians crest the top of a hill and come into the Ukrainian's sight, the Ukrainian can be heard asking the two Russian Soldiers to show him their yellow arm bands. This immediately put the Ukrainian at a loss of initiative, because it told the Russians he was a Ukrainian Soldier that didn't recognize them as an immediate threat.

As a result, the Ukrainian Soldier was killed in the ensuing gun battle with the two Russian Soldiers.

If a challenge and pass system was instead used to supplement IFF marking systems, the Ukrainian could have maintained the upper-hand throughout. He could have yelled the challenge term with his rifle aimed at the Russians, and then opened fire when they didn't know the answer. He even could have cycled through multiple previously used challenge terms from the past few weeks of combat operations to ensure that the Russians weren't Ukrainians coming back from a long range reconnaissance mission that had been out of the loop for several days.

All in all, this is just a bad situation. If you're one of the Ukrainians viewing our webpage, please encourage your troops to adopt a challenge and pass system.