Razak said Saturday that the plane was steered off course by someone on board, was airborne for more than seven hours and may have traveled as far as Kazakhstan. He added that although the movements were consistent with deliberate acts, he wouldn't confirm that the plane was hijacked.
Razak presented a vastly different timeline that what had officials had previously acknowledged -- saying for the first time that the last confirmed communication between the plane and a satellite was at 8:11 a.m. Malaysian time. The prime minister said the search has expanded to points as far north as Kazakhstan and as far south as the South Indian Ocean -- a stretch of more than 5,000 miles.
The flight was carrying 239 people when it disappeared while above waters between Malaysia and Vietnam. A frantic search followed, with 14 different countries involved.
The plane's communication systems were shut down separately, two U.S. officials said, an indication that the plane did not come out of the sky because of a catastrophic failure.
The data reporting system, they believe, was shut down at 1:07 a.m. The transponder – which transmits location and altitude – shut down at 1:21 a.m. The missing flight continued to "ping" a satellite on an hourly basis after it lost contact with radar, senior administration officials told ABC News.
ABC News' Matt Hosford and Michael S. James contributed to this report.