The US Navy has intercepted a large quantity of explosive materials being smuggled from Iran to Yemen along with what it describes as other lethal aid.

US Naval Forces Central Command Public Affairs said the US Coast Guard ship USCGC John Scheuerman and guided-missile destroyer USS The Sullivans intercepted a fishing vessel as it transited international waters in the Gulf of Oman on November 8. Patrol coastal ship USS Hurricane and Navy explosive ordnance disposal technicians from the US 5th Fleet’s Task Force 56 also assisted during a weeklong effort to fully search the vessel and verify the type of material found.

US forces discovered more than 70 tonnes of ammonium perchlorate, an oxidiser commonly used to make rocket and missile fuel as well as explosives. This is US 5th Fleet’s first ever interdiction of ammonium perchlorate.

“This was a massive amount of explosive material, enough to fuel more than a dozen medium-range ballistic missiles depending on the size,” said Vice Admiral Brad Cooper, commander of US Naval Forces Central Command, US 5th Fleet and Combined Maritime Forces.

The search also found more than 100 tonnes of urea fertiliser. Urea is a chemical compound with agricultural applications that is also known for use as an explosive precursor.

The vessel and its four Yemeni crewmembers were intercepted while transiting from Iran along a route historically used to traffic weapons to the Houthis in Yemen, the US Navy said. The direct or indirect supply, sale or transfer of weapons to the Houthis violates UN Security Council Resolution 2216 and international law, it noted.

US forces sank the vessel on November 13 in the Gulf of Oman after determining it was a hazard to navigation for commercial shipping. The four crewmembers were transferred to Yemen for repatriation on November 15 when The Sullivans completed an at-sea exchange in the Gulf of Aden with the Yemen Coast Guard.

“Alongside our partner forces, CENTCOM is committed to security and stability of the region and to deterring the illegal and destabilising flow of lethal material into the region over land, in the air and the sea,” said General Michael “Erik” Kurilla, US Central Command (CENTCOM) commander.

The US 5th Fleet previously seized 40 tonnes of urea fertiliser on January 18 when guided-missile destroyer USS Cole and patrol coastal ship USS Chinook interdicted another fishing vessel in the Gulf of Oman that had attempted to smuggle weapons off the coast of Somalia months earlier.

• A Tell report