Washington: Iranian Revolutionary Guard forces fired warning shots at a Singapore-flagged commercial ship in international waters in the Gulf on Thursday, before vessels from the UAE came to the ship’s aid, US officials said.

The Iranian patrol craft fired across the bow of the Alpine Eternity in international waters and the commercial ship then headed towards the UAE, two defense officials said.

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.

A US naval ship was 32 kilometers away from the Alpine Eternity but received no request for assistance, officials said.

The incident reflected rising tensions in the Gulf in recent weeks after Iran seized a Marshall Islands-flagged vessel and warned the United States not to interfere with an Iranian aid ship headed for Yemen. The commercial cargo ship was later released, after Iranian officials said a commercial dispute had been settled.

The Alpine Eternity is an oil-chemical tanker that had last stopped at a port in Bahrain, according to the marinetraffic.com shipping website. The ship is listed as part of the fleet of Transpetrol, a commercial shipping firm that transports oil and gas, with offices in Belgium, Bermuda, Norway and Switzerland.