Is it possible to have random image using Twine 2.0 Harlowe?

Pretty much the title. I'm trying to have it that either 1 of 3 pictures will show up randomly in the passage. Currently doing (either: <img src = "Source1">, <img src = "source2">) but its not working.

So is either only used to words/numbers? If so, would it be possible to make it so that it can be used for images?

Thanks