Douglas County sheriff’s detectives are looking into a report of a robbery Tuesday night in the Mrytle Creek area, a sheriff’s spokesman said today. A man called 911 shortly after 10:45 p.m. and reported finding his girlfriend in a residence tied up with zip ties, acccording to a dispatch report. The woman said she was tied up by a man and threatened with a knife. Dectives are seeking to confirm details of the report, the spokesman said. …