JERUSALEM -- A new report by a prominent Nazi-hunting group gives more than a dozen countries, including Hungary, Ukraine and Canada, low grades for bringing suspected Holocaust-era war criminals to justice.

The Simon Wiesenthal Center gave top marks to Germany - the first time any country besides the U.S. has been given an "A" grade for prosecuting suspected Nazi war criminals.

The Associated Press on Wednesday received an advance copy of the center's report, which covers the period between April 2009 and March 2010. The formal release is scheduled for Thursday.

The director of the Weisenthal Center's Israel office, Efraim Zuroff, said Hungary received a failing grade for not imprisoning Dr. Sandor Kepiro, a Hungarian military officer convicted in 1944 in the mass murder of civilians.

He called Canada's efforts "a terrible failure" for not extraditing former Nazis even after stripping them of citizenship.

The center gave a failing grade to Ukraine, saying it "has to the best of our knowledge never conducted a single investigation of a local Nazi war criminal, let alone prosecuted a Holocaust perpetrator."

But in a related development Wednesday, Ukraine rescinded the National Hero of Ukraine award given to Stepan Bandera, a nationalist partisan whose group briefly fought for the Nazis.

In all, nine countries received failing grades from the center and five received "Ds."

Zuroff noted that counterintuitively, perhaps, the number of new state-launched investigations has risen in recent years, even though 65 years have passed since the end of World War II.

A total of 456 new cases were opened in the period covered by the recent report, compared with 315 the year before and only 63 in 2006-2007.

Germany received its top mark for convicting, in 2009 and 2010, the first two Nazi war criminals since 2002.

"People assume because of the age of the defendants that nothing will actually happen," Zuroff said, but "passage of time does not diminish the crimes of the killers."

(This version CORRECTS that nine countries received failing grades, five others received "Ds." Adds quotes, byline, contributor's line)

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