Tajik soldiers
Media playback is unsupported on your device
Video

Tajik-Afghan US supply route security challenge

Forty percent of all supplies sent to US troops in Afghanistan are shipped via the north through Central Asia.

Unlike the main overland supply line through Pakistan, this route has been regarded as safe.

But as northern Afghanistan becomes increasingly unstable, it too may be under threat.

The BBC's Rayhan Demytrie reports from the Tajik-Afghan border.

Go to next video: Tajiks drawn into radical Islam