The US Navy seized hundreds of small arms, including AK-47s, from an unflagged boat in the Gulf of Aden, a US defence official said, according to Arab News.
Similar vessels intercepted in the same waters in recent years were shipping weapons to the Houthi militia in Yemen from their backers in Iran.
The defence official told Reuters that the incident took place on Tuesday and the boarding was carried out by the crew of the Jason Dunham destroyer. The unflagged vessel was a traditional dhow.
The defence official declined to comment on the destination of the small vessel, but it was being investigated.
He added that the US Navy and allied ships have carried out similar operations in the past, including seizing drugs from vessels in the area.
The Arab coalition, which is supporting Yemen’s government forces in the war against Houthi militia, has repeatedly accused Iran of shipping weapons, including ballistic missile components, to the group.
Weapons were seized by the US Navy from a dhow in 2016 that were believed to be on the way to Yemen.
In September, Vice Adm Kevin M Doneganthe, the top American navy commander in the Middle East, said Iran was smuggling illicit weapons and technology into Yemen, that enabled the Houthis to fire increasingly more sophisticated missiles into Saudi Arabia.
In 2016, the British-based Conflict Armament Research provided detailed evidence of the arms smuggling route between Iran and Yemen.
The group found that weapons seized from Iranian-made dhows by international warships in the Arabian Sea matched similar weapons captured from the Houthis.
In October 2016, US ships intercepted five Iranian arms shipments bound for Yemen.
The Gulf of Aden is one of the world’s busiest shipping routes connecting Europe to Asia and the Middle East, with Yemen to the north, Somalia to the south and the Arabian Sea to the east.