Three times: Make the panorama interactive with hotspots

I am trying to create a virtual tour with 3js using a 360 panoramic image using the following example with my own panoramic image:

http://web.mit.edu/hawksley/Public/IntroToWebVR/demo/

Everything does great, but I would like to make it much more interactive, i.e. create hotspots.

Let's say in the example above, if I add a hotspot icon and when I click on it, it goes to another 360 panoramic images.

Any idea or help on how this can be done? Any guidance would be appreciated. Many thanks