TOKYO - A Japanese national has been detained in Iran since last month, a senior government spokesman said Wednesday when asked about a report that the Tehran bureau chief of Japan's public broadcaster NHK has been arrested, saying the government is demanding the person's early release.

Radio Free Europe on Tuesday reported that Iran had arrested the Tehran bureau chief, citing two sources. It said that while it was unclear when he was arrested, he was taken to the capital's Evin Prison, where political prisoners are detained, on Monday.

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