Two missiles exploded in waters south of Yemen on Friday, maritime monitoring agencies said, following months of attacks on shipping by the country's Huthi rebels.
A Panama-flagged oil tanker "reported seeing two blasts" in the Gulf of Aden, said risk monitor Ambrey, a report that was corroborated by the British navy's United Kingdom Maritime Trade Operations. No damage was reported.
Ambrey said the missiles exploded about a mile from the India-affiliated oil tanker and 200-300 metres (650-1,000 feet) above the waterline. UKMTO said they detonated in the water.
"The target was unclear at the time of the report. There was no damage reported," Ambrey said, adding that vessels were calling for military assistance at the time.
Huthi attacks since mid-November have disrupted trade in the Red Sea, which carries around 12 percent of international maritime traffic, and triggered US and UK reprisal strikes.
The Iran-backed rebels say they are targeting Israeli-linked vessels in support of Palestinians in Gaza, which has been ravaged by the Hamas-Israel war that has inflamed tensions across the Middle East.
There was no immediate comment on the latest incident from the Huthis, who are part of the anti-Israel, anti-West "axis of resistance" of Iranian proxies and allies.
Several shipping firms have diverted away from the Red Sea, instead taking the longer and more expensive route around the Cape of Good Hope in South Africa.
It follows difficult years for the industry during the Covid-19 pandemic, when freight rates reached unprecedented levels due to blockages in supply chains.
The United States and Britain have carried out two rounds of joint strikes this month aimed at reducing the Huthis' ability to target shipping.
The US military has also launched a series of unilateral air raids on the rebels' missiles.
Washington is also seeking to put diplomatic and financial pressure on the Huthis, redesignating them as a terrorist organisation last week after dropping that label soon after President Joe Biden took office.
US warship downs missile fired at it from Yemen: military
A US Navy warship shot down a missile Friday that was fired at it by Yemen's Iran-backed Huthi rebels, who have carried out weeks of attacks on international shipping, the military said.
"Iranian-backed Huthi militants fired one anti-ship ballistic missile from Huthi-controlled areas of Yemen toward Arleigh-Burke class destroyer USS Carney (DDG 64) in the Gulf of Aden. The missile was successfully shot down by USS Carney," the US Central Command said in a statement on social media.