ADDIS ABABA (Reuters) - Ethiopian investigators cannot yet say whether there is a structural problem with the Boeing 737 MAX, based on flight and cockpit voice data from the plane that crashed on March 10 killing 157 people, the head of the investigation said.

“We will analyze whether other problems were existing on this aircraft,” Amdye Ayalew Fanta told a news conference in Addis Ababa on Thursday, adding this would take between six months and a year.

The Ethiopian transport minister said earlier that Ethiopian Airlines pilots had been unable to prevent the plane from repeatedly nosediving, despite having followed proper procedures as recommended by planemaker Boeing.