Kamal Hyder, Al Jazeera's correspondent in Peshawar, the capital of the NWFP said a "refugee disaster is now feared".
"This is a huge humanitarian crisis; the largest number of internally displaced people in the world, and in the smallest possible time," he said.
"Even in Darfur it took a considerable amount of time for the [number of internally displaced people] to swell up."
"It is going to be very difficult to separate the Taliban from the ordinary people," Hyder said.
"The Taliban also know they are fighting a losing battle and that without the support of the people they would not stand a chance."
Tens of thousands of Pakistani civilians in the Swat valley have found themselves trapped amid worsening fighting between government forces and the Taliban.
Bodies were reported to be lying in roads, homes reduced to ruins and people left cowering with no means of escape after the military imposed curfews across the region amid the fighting.
"Anger is growing that the government did not give the citizens adequate warning to escape," Hyder reported.
"Many people are saying their government has abandoned them ... what is unfolding here is the tip of the iceberg, the worst is yet to come."
Hundreds of thousands of civilians have already fled the fighting, many ending up in refugee camps.
Hyder said there was little government help available to those who had fled.