Overseas now to afghanistan and another alarming headline tonight. A man in an afghan police uniform shot dead one member of the u.S. Military and injured another. The latest in a surge of so-called... See More
Overseas now to afghanistan and another alarming headline tonight. A man in an afghan police uniform shot dead one member of the u.S. Military and injured another. The latest in a surge of so-called insider attacks. Ten u.S. Troops now have been killed by afghan security forces in just the past two weeks. Tonight here at abc news, we're on the ground in afghan with u.S. Troops there with a firsthand look at the new danger as one u.S. Captain works a room of angry afghans. Here is abc ap muhammad lila now. Reporter: We setff for a region so remote, so dangerous, that just last month we were ambushed here by the taliban. What you hear -- that's the afghan army, leading this fight and returning the fire. But increasingly, the biggest threat is no longer on the battlefield with yet another afghan policeman turning his weapon on u.S. Forces today and ten u.S. Troops dead in the last two weeks, afghans seem to be less friend than foe. Talk to me any time you need to. Reporter: A growing danger at bases like this where americans and afghans live side by side. We're on our way to meet the afghan commander of the this base. Many of his troops just left this morning on a dangerous mission and he's given us permission to tape a private briefing to update us on how the mission is going. Inside, the afghan commander is furious. His soldiers haven't returned and he doesn't know where they are. Captain marcus morgan is left to face that anger all alone. The only american in the room filled with afghans who are armed. This is how most insider attacks take place, with american troops completely vulnerable. What's it like walking into a room like that as the only american? As you develop personal relationships and work with the afghan counterparts on a routine basis you learn individual personalities and it becomes a much more comfortable situation. Reporter: That comfort is now shattered and the rules have changed. U.S. Troops have been ordered to carry loaded weapons with them at all times. A reminder that the taliban aren't just on the battlefield, they could also be in the same room. Muhammad lila, abc news. A bold message for the u.S.
This transcript has been automatically generated and may not be 100% accurate.