The sacking of the Vice President ED Mnangagwa alone was not the real trigger. The issue in my opinion was having a well decorated liberation hero having to hide in a neighbouring country due to fear of getting procecuted by mere ministers and also for fear of his life. The army l'm sure could not stand such a situation.
Vice President ED Mnangagwa
Most war veterans have been in support for the Vice President to take over from the old Mugabe and his sacking would mean all those in support would have to be sacked and removed from the revolutionary party for the same reasons the Vice president was sacked for.
General C Chiwenga
This would mean the revolutionary party would be devoid of the very people who made it what it is today. That alone is threat to gains of the liberation as is the excuse that is being used by the military to put the country on lock down.