All 157 people who were on board an Ethiopian Airlines flight that crashed en route to Nairobi, Kenya,  have died .  The  airline said in a statement  that the plane lost contact shortly after takeoff Sunday morning local time.

It isn't clear yet why it crashed.

Ethiopia Airlines says it believes there were 149 passengers and eight crew members on board, but it's double-checking the passenger manifest.  Search and rescue operations were ongoing as of Sunday afternoon local time.  Eight Americans  were among  the dead.  The  office of Ethiopia’s prime minister  expressed its "deepest condolences to the families of those that have lost their loved ones." Additional reporting from  Newsy affiliate CNN .