KUALA LUMPUR, Malaysia — A new analysis of satellite data indicates the missing Malaysia Airlines plane crashed into a remote corner of the Indian Ocean, Malaysian Prime Minister Najib Razak said today.

The news is a major breakthrough in the unprecedented two-week struggle to find out what happened to Flight 370, which disappeared shortly after takeoff from Kuala Lumpur to Beijing with 239 passengers and crew aboard on March 8.

But with the location of the plane itself still unknown — most likely somewhere at the bottom of the sea — profound questions remain about what brought down the aircraft and why.

Najib announced the news in a brief statement to reporters, saying the information was based on an unprecedented analysis of satellite data from Inmarsat.

He said the data indicated the plane flew “to a remote location, far from any possible landing sites.”

“It is therefore with deep sadness and regret that I must inform you that, according to this new data, Flight MH370 ended in the southern Indian Ocean.”

Najib said Inmarsat had done further calculations “using a type of analysis never before used in an investigation of this sort,” and had concluded that the plane’s last position was “in the middle of the Indian Ocean, west of Perth.”