South Korea is verifying reports of a possible attack on one of its vessels in the Strait of Hormuz, officials said Monday, adding that no casualties among South Korean nationals have been confirmed while authorities investigate the cause of a fire and assess damage.

The South Korean Foreign Ministry noted that there had been "no casualties involving South Korean nationals confirmed so far in the Strait of Hormuz.”

According to the media outlet Korea Herald, a South Korean-flagged cargo vessel anchored in the Strait of Hormuz "is believed to have been struck by an external impact.”

The vessel, identified as HMM Namu, was anchored outside the port limits of Umm Al Quwain, off the United Arab Emirates, when the incident occurred at around 8.40 pm South Korean time (1140GMT), it reported, citing South Korean authorities.

The report added that the vessel carries 24 crew members, including six South Koreans and 18 foreign nationals.

Earlier Monday, Iran said that two missiles struck a U.S. Navy vessel near Jask Island, located on the Gulf of Oman in southern Iran, but Washington denied the claim.

The developments come as Iran's Islamic Revolutionary Guard Corps earlier warned that any vessels violating transit protocols issued by Tehran in the Strait of Hormuz "will be forcefully stopped."

The US and Israel launched strikes against Iran on Feb. 28, triggering retaliation from Tehran against Israel, as well as U.S. allies in the Gulf, along with the closure of the Strait of Hormuz.

Since April 13, the U.S. has enforced a naval blockade targeting Iranian maritime traffic in the strategic waterway.

A two-week ceasefire became effective on April 8 through Pakistani mediation, followed by direct talks in Islamabad on April 11, while no agreement was reached on a lasting truce.

US President Donald Trump later extended the ceasefire without setting a new deadline, following a request from Pakistan.