Many times these trades are a result of the holder of the stock being in the box on margin - i.e. the person bought the stock on margin, and it dropped - (we all know that tcx has dropped). Anyway - the holder didn't answer the margin call by the time allotted, and the trader on the account automatically flushed enough stock out to cover the call. This is an automatic trigger point, and happens occasionally.
I am not saying this is absolutely what happened, but offer it as a possibility.