This article is well worth reading:

http://www.ekathimerini.com/237231/interactive/ekathimerini/special-report/hidden-children-of-wwii

I quote:

Father Chrysostomos also appears to have been betrayed by an informant. According to a witness, another Catholic priest, he was arrested by three men from the SS in the northern Athens suburb of Psychico in May 1944. According to the same witness, who is quoted by Father Giorgos in his book, as soon as Chrysostomos saw the Nazi officers coming, he swallowed a piece of paper with the names of certain Greek officers he had been planning to help escape to Egypt from the port of Rafina that very night. The Catholic priest was arrested and executed at the camp in Haidari on September 8, 1944. He was 32 years old.

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