Iranian police briefly detained two European diplomats at a mixed-gender party, which are illegal under Iranian law, the semi-official Tasnim news agency said Saturday.
A British and a Dutch diplomat were released in the early hours of Friday morning after being identified as foreign government workers.
The report said the party in the capital, Tehran, was attended by several men and women, but did not elaborate or specify if alcohol was present.
In Iran, it is illegal to drink alcohol or hold mixed gatherings of men and women who are not related.
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