WARSAW, Poland (AP) —  The Simon Wiesenthal Center's top Nazi hunter is applauding Polish prosecutors for deciding to seek an arrest warrant for a 98-year-old Minnesota man suspected of war crimes.

Efraim Zuroff told The Associated Press by phone from Jerusalem on Monday that "it's high time that the Poles became more active seeking people who committed crimes in World War II on Polish soil."

He says any legal step "sends a very powerful message."

Michael Karkoc was put under investigation after the AP published evidence in 2013 establishing he commanded a Nazi SS-led unit accused of burning villages filled with women and children. His family denies he was involved in any war crimes.

Germany shelved its own investigation of Karkoc in 2015 after concluding he was unfit for trial. Zuroff says independent doctors should re-assess him.

Karkoc's son says his father is unable to defend himself.

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