US Navy finds 'massive amount' of explosive material able to fuel over a dozen ballistic missiles on a fishing boat sailing from Iran

• The US Navy intercepted a fishing boat in the Gulf of Oman traveling from Iran to Yemen last week.
• During a search, the Navy found lethal aid and a "massive amount" of explosive material.

US Navy forces recently seized a "massive amount" of explosive material used to fuel ballistic missiles from a fishing boat sailing from Iran to Yemen, the service said on Tuesday.

The US 5th Fleet intercepted the vessel — and its four Yemeni crewmembers — crossing international waters in the Gulf of Oman on November 8, and a search of the ship led to the discovery of over 70 tons of ammonium perchlorate, which is a chemical compound used to make missile fuel and explosives, the Navy shared in a statement.

"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 Adm. Brad Cooper, who is the commander of US Naval Forces Central Command, US 5th Fleet, and Combined Maritime Forces.

"The unlawful transfer of lethal aid from Iran does not go unnoticed," he added. "It is irresponsible, dangerous and leads to violence and instability across the Middle East."

Last week's interception by the Coast Guard ship USCGC John Scheuerman and guided-missile destroyer USS The Sullivans marks the first such instance where Navy forces recovered ammonium perchlorate, the service said. Additionally, it said it found more than 100 tons of urea fertilizer, which can be used to make explosives.

The vessel was traveling along a route that has regularly been used to transit weapons to Iranian-backed Houthi rebels fighting against Yemen's government and its Saudi-backed coalition. The Navy said it sank the ship last weekend and transferred the crew to Yemen's Coast Guard.

Iran is the main supporter of the Houthis, who have fought a yearslong civil war against Yemen's internationally recognized government. Experts have often characterized the conflict as a proxy war between Iran and Saudi Arabia — two regional foes vying for regional influence.

"Alongside our partner forces, CENTCOM is committed to security and stability of the region and to deterring the illegal and destabilizing flow of lethal material into the region over land, in the air, and the sea," said Gen. Michael Kurilla, the commander of the US Central Command, in a Tuesday statement.

The interception comes after Western countries criticized Iran for its sale of explosive suicide drones to Russia, which has used the deadly systems in recent weeks to pound cities across Ukraine and target its critical infrastructure. It also comes as Iran faces increasing scrutiny on the domestic front over its treatment of protesters who have participated in large-scale anti-government demonstrations.