An Ethiopian Airlines jet has crashed shortly after take-off from Addis Ababa, killing all on board.
The airline said 149 passengers and eight crew members were on flight ET302 from the Ethiopian capital to Nairobi in Kenya.
The crash happened at 08:44 local time, six minutes after the months-old Boeing 737 Max-8 took off.
Another plane of the same model was involved in a crash less than five months ago, when a Lion Air flight crashed into the sea near Indonesia with nearly 190 people on board.
The cause of the disaster is not yet clear. However, the pilot had reported difficulties and had asked to return to Addis Ababa, the airline said.
"At this stage, we cannot rule out anything," Ethiopian Airlines CEO Tewolde Gebremariam told reporters at Bole International Airport in Addis Ababa.
"We cannot also attribute the cause to anything because we will have to comply with the international regulation to wait for the investigation."
Visibility was said to be good but air traffic monitor Flightradar24 reported that the plane's "vertical speed was unstable after take-off".
An eyewitness at the scene told the BBC there was an intense fire as the aircraft hit the ground.
"The blast and the fire were so strong that we couldn't get near it," he said. "Everything is burnt down."
The plane was delivered to Ethiopian Airlines on November 15 last year. It underwent a "rigorous first check maintenance" on February 4, the airline tweeted.
Mr Gebremariam told the news conference that passengers from more than 30 countries were on board the flight.
He said they included 32 Kenyans, 18 Canadians, nine Ethiopians, eight Italians, eight Chinese, eight Americans, seven Britons, seven French citizens, six Egyptians, five Germans, four Indians and four people from Slovakia.
One person held a UN passport, the airline said. It believed some passengers could have been heading to a session of the UN Environment Assembly which begins in Nairobi on Monday.
A UN source also told Agence France-Presse that "at least a dozen of the victims were affiliated with the UN", and that this may include freelance translators.
World Food Programme executive director David Beasley said seven members of agency staff had died in the crash.
Ethiopia has declared Monday a national day of mourning.
Canadian PM Justin Trudeau said he was "deeply saddened" to hear of the crash, adding: "We join the international community in mourning the loss of so many lives."
UK PM Theresa May tweeted her condolences:
António Guterres, the UN secretary-general, also tweeted about the crash.
The 737 Max-8 aircraft is relatively new to the skies, having only been in commercial use since 2017.
Boeing said it was "deeply saddened" by the crash and offered to send a team to provide technical assistance.
The anti-stalling system repeatedly forced the plane's nose down, despite efforts by pilots to correct this, findings suggest.