The devastating plane crash in Ethiopia could renew safety questions about the newest version of Boeing's popular 737 airliner.

The Boeing 737 Max 8 operated by Ethiopian Airlines crashed shortly after taking off from the capital of Addis Ababa on Sunday, killing all 157 people on board.

The plane was new. The weather was clear. Yet something was wrong, and the pilots tried to return to the airport. They never made it.

In those circumstances, the accident is eerily similar to an October crash in which a 737 Max 8 flown by Indonesia's Lion Air plunged into the Java Sea minutes after take-off, killing all 189 people on the plane. But safety experts cautioned against quickly drawing too many parallels between the two crashes.

Boeing Co said late Sunday it will postpone the planned ceremonial debut of its 777x widebody aircraft after the crash. The company is focused on "supporting" the airline and would not proceed with Wednesday's planned debut of the 777x in Seattle.

"We will look for an opportunity to mark the new plane with the world in the near future," the company said.

China's aviation regulator has ordered domestic airlines to suspend their Boeing 737 Max aircraft following the crash, Chinese media outlet Caijing reported.

Citing industry sources familiar with the matter, Caijing said Chinese airlines, which operate some 60 such airplanes, had received orders from the Civil Aviation Administration of China and halted their use on Sunday.

William Waldock, an aviation-safety professor at Embry-Riddle Aeronautical University, said suspicion will be raised because the same type of plane appeared to crash the same way - a fatal nosedive that left wreckage in tiny pieces.

"Investigators are not big believers in coincidence," he said.

Waldock said Boeing will look more closely at the flight-management system and automation on the Max. But he noted that it is very early, and more will be known after investigators find and analyse the Ethiopian plane's black boxes.

Alan Diehl, a former National Transportation Safety Board investigator, said the similarities included both crews encountering a problem shortly after take-off, and reports of large variations in vertical speed during ascent, "clearly suggesting a potential controllability problem" with the Ethiopian jetliner.

But there are many possible explanations, Diehl said, including engine problems, pilot error, weight load, sabotage or bird strikes. He said Ethiopian has a good reputation, but investigators will look into the plane's maintenance, especially since that may have been an issue in the Lion Air investigation.

By contrast, the Ethiopian Airlines CEO told reporters that a maintenance check-up did not find any problems with the plane before Sunday's flight, "so it is hard to see any parallels with the Lion Air crash yet," said Harro Ranter, founder of the Aviation Safety Network, which compiles information about accidents worldwide.

"I do hope though that people will wait for the first results of the investigation instead of jumping to conclusions based on the very little facts that we know so far," he said.

Boeing representatives did not immediately respond for comment. The company tweeted that it was "deeply saddened to learn of the passing of the passengers and crew" on the Ethiopian Airlines Max plane.

The Chicago-based company said it would send a technical team to the crash site to help Ethiopian and US investigators.

A spokesman for the NTSB said the US agency was sending a team of four to assist Ethiopian authorities. Boeing and the US investigative agency are also involved in the Lion Air probe.