At least three container ships were hit by gunfire ​in the Strait of Hormuz on Wednesday, maritime security sources ‌and the United Kingdom Maritime Trade Operations (UKMTO) said.

Iran has imposed restrictions on ships using the strait, first in retaliation for the US-Israeli bombardment of the ​country, and then in response to a US blockade of Iranian ports.

​A Liberia-flagged container ship sustained damage to its bridge after ⁠being hit by gunfire and rocket-propelled grenades northeast of Oman.

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The UKMTO ​said the master of the vessel reported being approached by an IRGC ​gunboat. The vessel, it said, was subsequently fired upon. All crew members were safe and there was no fire or environmental impact due to the incident.

Maritime security ​sources said that three people were onboard that gunboat.

The master of the Greek-operated container ​ship also reported that no radio contact was made before the incident and ‌that ⁠the vessel had been initially informed that it had permission to transit the Strait of Hormuz.

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The UKMTO later said that a second container vessel had been fired upon about eight nautical miles west of Iran. ​The Panama-flagged vessel was not damaged ​and its ⁠crew members are safe.

Maritime security sources said that a third container ship was fired upon about eight ​nautical miles west of Iran while transiting outbound of ​the Strait ⁠of Hormuz. The Liberia-flagged vessel, which was not damaged had stopped in the water. Its crew are safe, the sources said.

Before the war began on ⁠February 28, ​the waterway typically handled roughly one-fifth of ​the world’s oil and liquefied natural gas supply.