A group of government-appointed scientists warned Tuesday that a major earthquake in the Nankai Trough off the Pacific coast could leave as many as 1.45 million households in 246 coastal municipalities stranded.

The researchers who studied the effects of a potential mega-quake concluded such an event would affect more than four times the number of households than those forced to evacuate after the March 2011 earthquake and tsunami.

The number of households affected in 2011 is estimated at some 330,000.