First word of the crash came when Prime Minister Abiy Ahmed expressed his "deepest condolences" on Twitter.
The Office of the PM, on behalf of the Government and people of Ethiopia, would like to express it’s deepest condolences to the families of those that have lost their loved ones on Ethiopian Airlines Boeing 737 on regular scheduled flight to Nairobi, Kenya this morning.
— Office of the Prime Minister - Ethiopia (@PMEthiopia) March 10, 2019
In an earlier statement, the airline said that search and rescue operations were under way near the crash site around the town of Bishoftu, which is 60km (37 miles) south-east of the capital.
"Ethiopian Airlines staff will be sent to the accident scene and will do everything possible to assist the emergency services," the statement added.
Boeing, the company that built the aeroplane, said in a tweet that it was "closely monitoring the situation".
Its 737 Max-8 aircraft is relatively new to the skies, having been launched in 2016. It was added to the Ethiopian Airlines fleet in July last year.
The airline's highest fatalities prior to this came in a November 1996 crash during a hijacking on a flight from Addis Ababa to Nairobi.
One of the aeroplane's engines stopped when the fuel ran out and although pilots attempted an emergency water landing, they hit a coral reef in the Indian Ocean and 123 of the 175 people on board were killed.