A friend of the Goldin family, based in Britain, confirmed to the JC that Hadar, and his twin brother, had lived in Cambridge twice.
The friend, who did not want to be named, said the twins' parents were both Israeli, and did not believe that Hadar had taken up British citizenship. Their father, Dr Simha Goldin, is an academic specialising in Jewish studies, and had spent time on sabbatical at Cambridge University.
The family were active in Cambridge's Jewish community, taking roles in synagogue services there.
Barry Landy, of the Cambridge Traditional Jewish Congregation, confirmed the family had lived in the city twice.
"Hadar was a nice boy. The first time they came he was 12, the second time he was 15; on the second occasion he did his barmitzvah here," Mr Landy said. "The news is terribly shocking."
The British Foreign Office said it was urgently looking into the claims Lt Goldin had British citizenship.
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