PENTAGON --- The crews of two small U.S. Navy vessels being held by Iran will be released early Wednesday morning Gulf time, defense officials have told multiple news sources.
The 10 crew members — nine men and one woman — were traveling in the Persian Gulf between Kuwait and Bahrain when U.S. controllers lost contact with them.
"There may have been mechanical failure on one of the vessels, but it is unclear at this time," a defense official told VOA. "My assumption is that they were in Iranian territorial waters when they were detained."
The Pentagon said Iran had provided safety assurances and promised to "promptly allow [the crews] to continue on their journey."
But VOA's Persian service said that the Iranian news service, the Fars news agency, was reporting that the crew members had been "arrested."
U.S. officials said the incident happened in the Persian Gulf near Farsi Island, located about halfway between the gulf coast of Saudi Arabia and the Iranian mainland.
Farsi Island is home to an Iranian Revolutionary Guard Corps naval base, which may be why the sailors were quickly detained, Matthew Kroenig, a senior fellow in the Atlantic Council’s Brent Scowcroft Center on International Security, told VOA Tuesday.
“Most countries would do the same thing if foreign sailors came that close to a naval base,” Kroenig explained.
The news came less than a month after U.S. officials accused Iran of conducting a "highly provocative" rocket test near U.S. boats passing through the Strait of Hormuz.
A senior administration official said Secretary of State John Kerry spoke by telephone at midday Tuesday with his Iranian counterpart, Mohammed Javad Zarif, shortly after the incident unfolded.
The detention also came just hours before President Barack Obama was to deliver his final State of the Union address to Congress and the public. Part of his speech was expected to address congressional concerns about a nuclear agreement reached last year between Tehran and Western powers.
The deal is set to curb Iran's nuclear program in return for Western governments' lifting of long-standing economic sanctions against the Islamic Republic.