How Many Real Palestine Refugees?

A "refugee from Palestine" is someone who could prove he/she was in the territory of the Palestine Mandate from two years prior to the 1948 war:

Palestine refugees are defined as “persons whose normal place of residence was Palestine during the period 1 June 1946 to 15 May 1948, and who lost both home and means of livelihood as a result of the 1948 conflict.” 

Now, consider this:

Jerusalem (Feb. 4, 1946)
There are at present more than 10,000 Arabs in Palestine who entered the country illegally, an official Government estimate revealed today. Most of these illegal immigrants are concentrated in the Haifa district, the Government said.

If there were 10,000 illegal Arab residents in 1946, I presume there were more by the end of 1947 and that would mean that in addition to the ridiculously short time period, much shorter than that most countries demand as a requirement for citizenship, the numbers of refugees today is inflated.

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