Walker said he and his comrades walked more than 100 miles en route to the northern city of Konduz.

CNN: Walker: Prison uprising was 'mistake'

He was discovered after he survived a prison uprising in which hundreds of non-Afghan Taliban fighters had been taken prisoner after surrendering at Konduz.

CNN: Sources: American Taliban fighter says new attack planned on U.S.

But a top Taliban leader who had been negotiating with Dostum for the surrender of Konduz said the rebellious prisoners were mostly non-Afghan fighters who acted on their own.

CNN: Taliban prisoner revolt crushed, cleanup begins