Editor's Note: This article originally appeared on Radio Free Europe/Radio Free Liberty.

A U.S. Navy veteran being held in Iran has been detained in connection to a “private complaint,” an Iranian prosecutor says.

Michael White, 46, has been held since July, and is the first known American to have been detained in Iran since Donald Trump became president two years ago.

Iran's semiofficial Mehr news agency on January 25 quoted prosecutor Gholamali Sadeqi as saying the case was still “under investigation,” without elaborating. He did not confirm reports that the man faces security charges.

Iranian Foreign Ministry spokesman Bahram Qasemi earlier this month confirmed White's arrest, which had been first reported by The New York Times on January 7, but did not specify when it had happened or what crime he was accused of.

The newspaper quoted White's mother, Joanne, as saying her son had visited Iran “five or six times” to see an Iranian woman she described as his girlfriend.

White's detainment was also reported on January 7 by Iran Wire, an online news service run by Iranian expatriates.

Iran in the past has detained Westerners and dual nationals to use them as leverage in negotiations.

Tensions have been high since Trump pulled Washington out of a landmark nuclear deal with Iran and reimposed crippling economic sanctions against Tehran last year.

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