[1] A member of the faction opposed to Lieutenant Colonel Mengistu Haile Mariam, Mogus was appointed to chair a committee to reorganize the Derg.
This committee proposed a new structure which included: a Congress which included all of the members of the Derg, to act as its legislature; a Standing Committee of 17 members, to act as its executive; a group of 40 members who act as a go-between, which Rene LaFort believes was "established, so it seems, to calm the fears of the other ranks in the Derg who had always been afraid of being edged out of power"; and a detailed enumeration of the powers of the two Vice-Chairmen of the Derg.
[2] If it was not clear by this point to Mengistu that he was being squeezed out of power, after a mass rally in Revolution Square in Addis Ababa (better known by its older name, Meskel Square, which was later restored after Mengistu's fall), when General Tafari Benti gave a speech for reconciliation between the various revolutionary factions, he was flanked by Captains Almayahu Haile and Mogus.
[3] At a February 1977 meeting between Mengistu and his opponents, that included not only Mogus but chairman General Tafari Benti and a number of leading members of the Derg, military soldiers under the command of Lieutenant Colonel Daniel Asfaw rounded up and arrested him along with other Derg members suspected of conspiring with EPRP.
Mengistu afterwards broadcast on Radio Ethiopia that Mogus and his dead compatriots had attempted a "fascist coup d'etat in the capital identical to what had taken place in Chile", and labeling them "fifth columnists" of the Ethiopian Democratic Union and Ethiopian People's Revolutionary Party rebel groups.