Under worldwide rules, responsibility for leading the crash investigation lies with Ethiopian authorities, while the US National Transportation Safety Board (NTSB) will automatically take part because the Boeing aircraft was designed and built in the United States.
The reason for the crash is not yet known.
The Ethiopian plane was new, delivered to the airline in November.
Ethiopian Airlines, a state-owned company, is recognized as one of the continent's most successful carriers.
He had an "excellent flying record", according to the CEO.
Anxious families gathered at the flight's destination, the airport in Nairobi, the capital of neighboring Kenya. CS James Macharia said a team led by Principal Secretary Esther Koimett has been sent to Ethiopia.
"No, we haven't seen anyone from the airline or the airport", he told Reuters at 1pm, more than three hours after the flight was lost. The victims include 32 Kenyans, 18 Canadians, nine Ethiopians, eight Italians, eight Chinese, eight Americans, seven British citizens, seven French citizens, six Egyptians, five Dutch citizens, four Indians, four Slovakians, three Austrians, three Swedes, three Russians, two Moroccans, two Spaniards, two Poles, two Israelis and two Nigerians.
Kevin Durant suffers right ankle injury, leaves Warriors' loss to Suns
National Basketball Association favorites of 17 points or more had gone 85-1 in the last 20 seasons, according to ESPN . Last night, the Warriors gave up a 16-point first-half lead and could not contain Devin Booker .
"It is believed that there were 149 passengers and eight crew on board the flight but we are now confirming the details of the passenger manifest for the flight".
The jet's last maintenance was on February 4, and it had flown just 1,200 hours.
The crash shattered more than two years of relative calm in African skies, where travel had always been chaotic.
Sunday's crash comes as the country's reformist prime minister, Abiy Ahmed, has vowed to open up the airline and other sectors to foreign investment in a major transformation of the state-centred economy.
"A Boeing technical team is prepared to provide technical assistance at the request and under the direction of the US National Transportation Safety Board".
The plane, which crashed shortly after takeoff from Addis Ababa, had 149 passengers and eight crew members on board, the airline said.
- March 2018: More than 50 people were killed when a US-Bangla Airlines flight from Dhaka, Bangladesh, crashed at the airport in Kathmandu, Nepal's capital.