By Nathan Morley
Security forces have deployed in strength across the Ethiopian capital, Addis Ababa.
Internet access and some telephone circuits have been blocked.
The personal bodyguard of General Seare Mekonnen - the chief of staff of the Ethiopian army – shot him dead after he and another officer attempted to prevent a coup against the administration in the northern Amhara region.
A little earlier, the regional governor of Amhara was killed along with an aide.
A government spokesman said that many of those involved in the coup attempt have been arrested and operations are in progress to find others.
Ethiopia has been struggling to contain widespread ethnic violence, which the United Nations says has displaced over 2 million people.