After a week of false leads, U-turns, wild speculation and outright contradictions, it was hard to believe there could be any more surprises in the hunt for the missing Malaysia Airlines flight.

But when Malaysian Prime Minister Najib Razak finally appeared before the media Saturday afternoon — almost 45 minutes later than scheduled and for the first time since Flight MH370 went missing seven days before — his words were startling.

Not only did investigators believe the plane had been deliberately diverted after its communication systems were switched off, but they believed it had been sending signals to satellites from air or ground as late as 8:11 a.m. on March 8, more than 6½ hours after it had lost contact with air control staff and 45 minutes after the Boeing 777 had been declared missing in a statement from the airline.