internment camp vs prison camp

internment camp and prison camp both are nouns.

Word	Noun	Adjective	Verb	Adverb
internment camp	Yes	No	No	No
prison camp	Yes	No	No	No

As nouns, internment camp and prison camp are synonyms defined as:

Other synonyms of internment camp include POW camp, prisoner of war camp.

internment camp (noun)	prison camp (noun)
a camp for prisoners of war	a camp for trustworthy prisoners employed in government projects
	a camp for prisoners of war