How to label a loading animation for WAI-ARIA?

I believe the most sensible approach would to use the combo aria-busy="true" aria-live="polite"

The reason for that is because some pages might have a lot of separate loaders (let's say one for each component, not a single loader for the whole page) and it you use aria-live="assertive" or role="alert" it will be very intrusive and each of the loaders will get called out.

The best solution I could come up with was using role alert, and aria-busy="true".

<div id="loading" style="display: none;">
    <div class="mgBot15"><span class="txt16" role="alert" aria-busy="true">Working...</span></div>
    <img src="loading.png" alt="loading" />
</div>