More than 300 Nazi persecutors have been deported, stripped of citizenship or blocked from entering the United States since the creation of the O.S.I., which was merged with another unit this year.

In chronicling the cases of Nazis who were aided by American intelligence officials, the report cites help that C.I.A. officials provided in 1954 to Otto Von Bolschwing, an associate of Adolf Eichmann who had helped develop the initial plans “to purge Germany of the Jews” and who later worked for the C.I.A. in the United States. In a chain of memos, C.I.A. officials debated what to do if Von Bolschwing were confronted about his past — whether to deny any Nazi affiliation or “explain it away on the basis of extenuating circumstances,” the report said.

The Justice Department, after learning of Von Bolschwing’s Nazi ties, sought to deport him in 1981. He died that year at age 72.

The report also examines the case of Arthur L. Rudolph, a Nazi scientist who ran the Mittelwerk munitions factory. He was brought to the United States in 1945 for his rocket-making expertise under Operation Paperclip, an American program that recruited scientists who had worked in Nazi Germany. (Rudolph has been honored by NASA and is credited as the father of the Saturn V rocket.)

The report cites a 1949 memo from the Justice Department’s No. 2 official urging immigration officers to let Rudolph back in the country after a stay in Mexico, saying that a failure to do so “would be to the detriment of the national interest.”

Justice Department investigators later found evidence that Rudolph was much more actively involved in exploiting slave laborers at Mittelwerk than he or American intelligence officials had acknowledged, the report says.

Some intelligence officials objected when the Justice Department sought to deport him in 1983, but the O.S.I. considered the deportation of someone of Rudolph’s prominence as an affirmation of “the depth of the government’s commitment to the Nazi prosecution program,” according to internal memos.