Five Iranian naval vessels fired on a Singapore-flagged cargo ship sailing through the Straits of Hormuz CNN reported today, citing a U.S. official.

It is not yet clear if any of the rounds hit the Alpine Eternity. There were no U.S. citizens or cargo on board. The Pentagon is still gathering information about the incident.

The incident began when five small fast boats, believed to be manned by Iran’s Revolutionary Guard Corps Navy approached the cargo vessel just off the coast of the United Arab Emirates but in international water, the official said. ….

The incident began with the Iranians ordering the ship into Iranian waters. When the ships master refused, the Iranians began to fire in a way to try to disable the ship, not just as warning shots, the U.S. official said.

While several shots were reported to have hit the ship, it was not disabled.

Agence France-Presse added that the Alpine Eternity called for help from the United Arab Emirates.

The Alpine Eternity issued a radio call for help to the UAE and the Iranian boats fired a second wave of warning shots, the officials said.

UAE authorities heard the radio call and deployed coast guard boats in response. The Iranian boats then departed the area, the officials said.

Following the seizure at sea of the Maersk Tigris in late April, the United States began providing escorts to ships passing through the Straits of Hormuz, but recently stopped the practice. The illegal seizure of the Tigris was one of a number of recent Iranian challenges to the American navy in the Persian Gulf. The Tigris was released after the Maersk shipping line agreed to settle a claim made against it by an Iranian company.

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