Co-pilot's cell phone signal detected after Flight 370 vanished from radar

A signal coming from the cell phone belonging to Flight 370's co-pilot reached a Malaysian cell tower in the moments after the plane lost contact. The tower was about 250 miles from the location of the flight's final signal. It is raising serious questions about how far off course and how low the plane was flying. Pamela Brown has the latest on the investigation.

Martin Savidge takes a look at what this cell phone data says about Flight 370's altitude.