The nose of a Boeing Co. 737 MAX 9 jetliner sits during production at the company's manufacturing facility in Renton, Washington. David Ryder | Bloomberg | Getty Images

Flight data recovered from the wreckage of an Ethiopian Airlines jet showed "clear similarities" to another deadly crash of one of Boeing's top-selling 737 Max aircraft last October, according to the French accident investigator that downloaded the information. Ethiopian Airlines Flight 302, a Boeing 737 Max 8, went down shortly after takeoff from Addis Ababa on March 10, killing all 157 people on board. That occurred less than five months after a Lion Air jet crashed into the Java Sea in Indonesia during a similar stage in its flight, killing all 189 passengers and crew. Both 737 Max 8 jets were delivered to the airlines just months before their fatal flights.

The U.S. on Wednesday joined dozens of other countries in ordering airlines to ground the planes after the Federal Aviation Administration said it found new evidence that may link the two crashes. Investigators who verified the data from the doomed Ethiopian Airlines jet's flight data recorder found similarities between the Lion Air and Ethiopia crashes, "which will be the subject of further study during the investigation," French accident authority BEA said in a statement Monday. That echoed statements from Ethiopian Transport Minister Dagmawit Moges a day earlier. Data from the other black box — the cockpit voice recorder — has also been extracted and has been handed over to Ethiopia's accident investigator, BEA said. The U.S. National Transportation Safety Board, which is participating in the investigation of Ethiopian Airlines Flight 302, also verified the data, BEA added. Scrutiny has increased on the federal approval process for the new Boeing Max jets, which have been flying for less than two years.