The crimes are said to have taken place more than 70 years ago.

Prosecutors in Poland are formally seeking the extradition of a 98-year man living in Minnesota who has been accused of being the former head of an SS-led Nazi unit that slaughtered civilians and set fire to Polish villages.

Ben Keith comments:

Ben Keith, a barrister at the London chambers of 5 St Andrews Hill, said Mr Karkoc’s extradition would be governed by the EU-US extradition treaty.

“The terms of the agreement mean that Poland is not required to produce the evidence of the crime, merely that it provides a summary of the evidence,” he told The Independent in a statement. “Based on mutual trust and recognition, the US can be expected to extradite Mr Krakoc unless there prove to be obstacles.”

Mr Keith said there were various potential obstacles to such a move. He said one possible issue, the lapse of time, was unlikely to be relevant because of the nature of the crime involved. However, Mr Krakoc’s reported ill-health could prove crucial.

“The question will therefore be whether he is fit to travel to Poland, and more importantly whether he is fit to stand trial,” he said. “Does he have sufficient mental capacity to understand the case against him? That will be for the US courts to decide.”