I wonder why they added quotation marks around "coup" in the headline? Is there anything nonstandardly-coupish about a military commander engaging in armed rebellion to overthrow the standing government? Seems to perfectly fit the textbook/dictionary definition of "coup".
For now it is "only" an armed rebellion, I guess. And depending on how it unfolds it could be a lot of things.
I think that this sort of thing is not very frequent in contemporary, or even modern, history, but it is very reminiscent of Roman history.