German investigators trying to track down Nazi criminals before they die may have had their “best break” in years after discovering a trove of Brazilian immigration files more than half a century old.

Kurt Schrimm, the top German justice official hunting Nazi fugitives, said his team stumbled on archives identifying “several hundred” Germans who moved to Brazil in the decade after World War II and who may be linked to Nazi crimes. Though only a fraction is still likely to be alive, Schrimm plans to follow up on the lead with Brazilian officials.

“The discovery will probably be our most important find in recent times,” Schrimm said in an interview Nov. 24 from his office in the southwestern German city of Ludwigsburg. Schrimm kicked off research in Brazil in July and will report again on findings after his team returns there in March.

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