MADELEINE McCann was abducted by an accomplice of prime suspect Christian B and sold to him, it has been suggested.
The theory was recognized by the prosecutor who built a case against the convicted rapist and pedophile.
Hans Christian Wolters told Portuguese TV investigator Sandra Felgueiras he could not comment on the speculation.
But when she pressed him to find out if the three-year-old had been sold to the suspect, he replied: “Maybe, that’s a possibility.”
Madeleine disappeared from her family’s holiday apartment in the Algarve at Praia da Luz in 2007.
The German, 45, has been named the prime suspect – but detectives are believed to be hunting a wandering friend.
Sources in Portugal say investigators are certain the sex offender killed Madeleine but did not act alone.
Christian B denies any involvement in the disappearance of the British child.