As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE IN FLIGHT AT FL200, BOTH PILOTS NOTED SMOKE AND FUMES IN THE CABIN. BOTH BLEEDS WERE TURNED OFF AND THE SMOKE SUBSIDED. THE ACFT WAS RETURNED TO THE DEPARTURE POINT WHERE AN UNEVENTFUL LANDING WAS MADE. TROUBLESHOOTING IS ON-GOING.