He was convicted in 2010 and sentenced to life in prison by a German court for the murder of three Dutch civilians in 1944, DutchNews.nl reported Monday.
A native German, Boere's family moved to the Netherlands when he was 2 years old. He joined the Waffen SS in 1940 and was involved in killing members of the Dutch resistance.
Captured by Americans after the war, he escaped from a Dutch prison camp in 1949 and hid at his mother's home in Maastricht for seven years. A Dutch court tried him in absentia and sentenced him to death. Boere fled to Germany in 1954.
He died Sunday in a prison hospital in North Rhine-Westphalia, Dutch TV NOS reported.
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