U.S. aviation experts on Tuesday joined the investigation into the crash of an Ethiopian Airlines jetliner that killed 157 people, as a growing number of airlines grounded the new Boeing plane involved in the crash.

The investigation into the Ethiopian Airlines crash is in its early stages and there is no need to issue new guidance to operators of its 737 MAX 8 aircraft based on the information it has so far, Boeing said on Monday.

Of the Ethiopian Airlines crash, Prime Minister Justin Trudeau said Canada "joins the international community in mourning the loss of so many lives."