The families of passengers and crew aboard Ethiopian Airlines Flight 302 will mark the first anniversary of the crash on Tuesday, a day after the release of an interim report focused on software installed on the Boeing 737 Max airliner.

The accident killed all 157 people aboard. It was the second involving the new 737 Max plane in just five months and led to its worldwide grounding.

There were people from 33 nations aboard Flight 302. Hundreds of relatives and friends from across the world have traveled to Ethiopia for the memorial.

Families from nations including Canada, the United States, Ethiopia, Kenya, Uganda, Italy and France will attend the ceremony at the crash site, which is about a three-hour drive from the capital, Addis Ababa.

Organizers say the program will include a tree planting and the reading out of victims' names.

The 737 Max, Boeing's best-selling plane, remains grounded. Boeing has lost billions of dollars in the wake of the Ethiopian crash and an October 2018 accident involving Indonesia's Lion Air which killed all 189 people aboard.

Boeing's CEO was forced to step down and the company is facing hundreds of lawsuits from bereaved families.

Monday's interim report from Ethiopia's Aircraft Accident Investigation Bureau bolstered the findings of Ethiopia's initial assessment, which linked the crash to the plane's MCAS anti-stall software.

It identified no issues with the airline or the pilots' handling of the plane, which crashed shortly after take-off.

Inaccurate sensor readings activated the plane's MCAS anti-stall system, pushing the nose of the aircraft lower as the pilots struggled to control it, the report said.