Strange internal links appearing in documents

I’m getting odd random links appearing in a project I’m working on. They’re not links that I’ve added (at least not that I’m aware of) and don’t seem to go anywhere if I click on them. Example below, including tool tip showing link. I also can’t remove them – Edit > Remove link doesn’t do anything. Cutting and re-pasting the text doesn’t remove the link. The only way to get rid of them is to copy and paste into a plain text editor, delete the original, then copy and paste back from the text editor back into Scrivener.

If I compile to Word the link remains though it doesn’t appear as a hyperlink. It can, however, be removed using Word’s ‘Remove Link’ command.

Can anyone shed any light on what’s going on here?