Bloomberg and Reuters are picking up on this report from al-Arabiya, which at least thus far appears unconfirmed by other sources. As Bloomberg’s anchor notes here, though, the Iranian foreign minister has just made an unplanned change to his schedule:

Iranian forces seized a U.S. cargo vessel, Saudi-owned Arabiya television reported, without saying where it obtained the information. Iranian forces took the vessel to the Persian Gulf port of Bandar Abbas, the television station said.

Reuters expanded on the initial flash, and now reports that the Iranian vessel “opened fire” on the US ship:

The channel said the force had “opened fire” on the U.S. ship, which had 34 U.S. sailors aboard. It gave no further details. The U.S. Fifth Fleet in the Gulf Arab kingdom of Bahrain had no immediate comment on the report.

But is the story accurate? CNBC says that the US Navy denies that a confrontation took place, but they are talking about Navy ships only:

A U.S. vessel has been fired on and steered to the Bandar Abbas port by Iran on Tuesday, according to reports by the Saudi news network, Al Arabiya. Iran’s Fars News Agency also reported that an “American trade vessel” had been confiscated.

Senior U.S. Navy officials told NBC News there had not been any confrontation between Iran’s Revolutionary Guard and any Navy ships, however.

That’s not the same thing as refuting the al-Arabiya report, although it’s certainly no confirmation of it, either.

Update: The Pentagon has confirmed the seizure:

BREAKING: Iranian forces have boarded the Marshall Island-flagged MV Maersk Tigris in the gulf, Pentagon says

— Reuters (@Reuters) April 28, 2015

Update: Consider this my civics lesson for today. The Republic of the Marshall Islands is independent of the US but has a “free association” relationship with us. I’ve added the note to the headline. However, since we provide for the defense of the Marshall Islands, it’s going to wind up functionally the same thing. (Maersk is a Danish shipping firm, it’s worth noting.) Thanks to Jeryl Bier for the clarification.

Update: The Pentagon admits that the ship crossed into Iranian waters:

Cargo ship was in #Iran waters, DoD spokesman says. Ship wasn't U.S.-flagged vessel, and no Americans on board, says spokesman Warren.

— Terry Atlas (@TerryAtlas1) April 28, 2015

That’s an interesting position to take so quickly. Did they track the ship crossing the line, or just want to avoid a military confrontation? This looks like a washing of the hands type of statement.

Update: The Pentagon further states that they attempted to assist the ship, but only from international waters:

MORE: Pentagon: After distress signal, USS Farragut dispatched to assist ship from international waters: https://t.co/zPwpYHqInk

— ABC News (@ABC) April 28, 2015

Pentagon: Iran fires warning shots near Marshall Islands-flagged ship after failure to comply to request to go deeper in territorial waters.

— ABC News (@ABC) April 28, 2015

The Iranians are on board now:

#Maersk Tigris cargo ship w/US crew detained near Iran. According to @ReutersWorld Iranian forces have boardet the ship. #breaking #Iran #US

— Tinne Hjersing Knudsen (@Tinnehjersing) April 28, 2015

We’ll see what the Iranians claim to find.

Update: Morgen Richmond reminded me via e-mail that any ship passing through the Strait of Hormuz could be considered within Iranian territorial waters.  It’s not clear that’s where the ship was, at least not yet, and the US has usually not accepted that claim from Iran.

Update: According to NBC News, the Maersk Tigris was approaching the Strait of Hormuz but not yet within it:

The ship, the Maersk Tigris, was in Iranian waters, preparing to enter the Strait of Hormuz, which connects the Persian Gulf to the Arabian Sea, the officials said.

From which side?

Update: According to the site MarineTraffic.com, it looks like the Maersk Tigris came right down the middle of the strait, but then shifted north:

@EdMorrissey RE: Maersk Tigris. You can see recent position and track here: http://t.co/Ngzrpqg7PW pic.twitter.com/bXaj5fbUX5

— Steve Lewis (@siwel_evets) April 28, 2015

@EdMorrissey You can also see the time that the ship started veering north. pic.twitter.com/QRnesV0Q2X

— Steve Lewis (@siwel_evets) April 28, 2015

Was that prior to the Iranian intercept, or because of it? If prior, then the Pentagon statement makes some sense. That little knuckle in the track in the second image would appear to correspond with an attempt to maneuver back into international waters.

Update: According to al-Jazeera, the Iranians have released the Maersk Tigris.

https://twitter.com/zaidbenjamin/status/593085549549858816

Makes one wonder what this was all about.