Yemen’s Breakthrough against Iran’s Arms Smuggling to the Houthis

On July 16, 2025, the Yemeni National Resistance Forces (NRF), a coalition of anti-Houthi forces led by General Tareq Saleh and operating under the authority of the Presidential Leadership Council (PLC), the internationally recognized government of Yemen, seized over 750 tons of Iranian-supplied munitions and military hardware bound for the Houthis.

The interdiction represents the largest seizure of Iranian lethal aid bound for the Yemeni insurgent group, underscoring the scale of Iran’s ongoing military support to the Houthis. It also marks a notable evolution in the capacity of local Yemeni forces to counter such threats without assistance from the United States or other actors.

A Floating Arsenal

The recent seizure marks a watershed moment in the longstanding shadow war playing out in the Red Sea. The arsenal found on board the Boom-type dhow is notable both for its scale and sophistication; though interdictions of Iranian smuggling dhows by Western navies have taken place with increasing frequency over the last five years, few have matched the operational value of the materials seized in this latest operation.

Initial assessments, corroborated by open-source imagery, identify a diverse array of components for Al Mandab 2 anti-ship cruise missiles and Type 358 surface-to-air missiles with which the Houthis have targeted military and commercial vessels transiting in the Red Sea region since November 2023. The illegal haul also included Ghaem-118 interceptors, an anti-drone missile recently unveiled by Iran. Yemeni soldiers also discovered bags of nitrogen fertilizer, a well-known precursor for explosives, onboard. Notably, the absence of complete missile bodies reinforces suspicions that the Houthis operate assembly lines and employ technically trained personnel capable of final-stage assembly in the areas the group controls.

Among the stockpile of lethal aid, there were also radars and electro-optical/infrared sensors vital to the construction of explosive-laden drones and nearly one hundred twin-cylinder UAV engines compatible with the Shahed-131 and 136 models. Additionally, the haul included launch rails and critical command-and-control (C2) equipment for drone warfare, such as ruggedized laptops, Ground Control Station units, telemetry modules, and servers. Finally, alongside missile and drone components, there was military gear designed for ground and urban warfare, including Dehlavieh anti-tank guided missiles (ATGMs), Misagh-type man-portable air defense systems (MANPADS), sniper rifle accessories, binoculars, and thermal optics.

If there were any doubt as to the origin of the dhow’s contents, the inclusion of technical manuals in Farsi and packaging bearing marks associated with the Iranian military would appear to confirm the shipment’s provenance. Moreover, it suggests either the direct involvement of IRGC operatives or the operational presence of Iranian-trained, Farsi-speaking Houthi personnel on the ground.

What’s So Different This Time?

This operation stands apart from previous seizures of weaponry destined for the Houthis. Western naval forces operating under the Combined Maritime Forces (CMF), a U.S.-led multinational maritime partnership, especially Task Force 150, often capture smaller Iranian weapon and narcotic shipments to the Houthis. In May 2025, the U.K. Royal Navy’s frigate HMS Lancaster seized a cargo of illegal narcotics, which included 1000 kg of heroin, 660 kg of hashish, and 6 kg of amphetamine, while patrolling in the Arabian Sea.

However, those actions rarely approached the strategic breadth or logistical intricacy seen in the July interdiction, and they certainly fell short in terms of the capabilities they denied the Houthis. The July 16 haul was not simply a weapons shipment, but a floating toolkit intended to sustain and evolve the Houthis’ ability to threaten shipping lanes. The inclusion of newly developed Ghaem-118 interceptor missiles underscores Iran’s apparent intent to use Yemen as a proving ground to field-test its emerging weapon systems in combat.

Most importantly, the components seized in this interdiction would have helped replenish the stocks depleted by the Houthis over the past year, as the group conducted strikes against maritime traffic in the Red Sea and Gulf of Aden. The recent resurgence of attacks on international shipping illustrates that the Yemeni armed militia still retains significant offensive capabilities to hold regional maritime routes hostage.

The Deepening Iran-Houthi Partnership

Indeed, this maritime interdiction takes on added significance in the context of the recent operational uptick in Houthi at-sea combat activities. After a seven-month lull in hostilities, the Houthis have been responsible for the recent sinking of two commercial ships, the Magic Seas and the Eternity C.

Despite Tehran’s public denial that it supports the Houthis, the IRGC and Iran’s defense-industrial network clearly have a hand in these attacks. The inclusion of Type 358 missiles, developed by Iran for asymmetric air defense, and the use of uniquely Iranian electronic warfare systems confirm that this was a deliberate and centrally coordinated effort by Iran to re-arm its Houthi partners for sustained offensive maritime operations, which draw a great deal of attention from the United States and its regional partners.

Iran’s strategic calculus appears rooted in its desire to leverage the Houthis as a forward operating force capable of projecting pressure on international trade routes without requiring Tehran’s direct involvement. By maintaining a plausible degree of separation—despite overwhelming forensic evidence of its material involvement—Iran’s leaders are able to deny responsibility while maximizing the regional and global impact of Houthi aggression. The Houthis have therefore evolved from a domestic insurgent group to a critical node in Iran’s network of strategic depth. Their ability to strike international shipping, disrupt commerce, and bait U.S. and European military responses provides Tehran with a valuable pressure point, particularly as negotiations over its nuclear program remain frozen.

The Case for Strengthening Local Capabilities

The success of Gen. Saleh’s maritime units highlights the underappreciated role that local Yemeni forces can play in countering Iranian smuggling networks. Unlike previous high-profile interdictions led by Western navies, the July 16 operation was the product of Yemeni-led intelligence, coordination, and maritime patrol capacity. It signals a potential turning point in which the internationally-recognized Yemeni government can take greater ownership of security enforcement, provided it is given the tools, training, and strategic backing to do so.

July’s interdiction follows a series of other, smaller seizures over the past months. On July 11, NRF forces intercepted a small fishing boat carrying weapons, including anti-tank munitions, RPGs, and sniper rifles—more typical fare for the Houthis’ land campaign against PLC-aligned forces. The limited cargo and seakeeping capacity of the intercepted boat suggests that it received the weapons from a larger dhow and was transporting the lethal aid to land. Three days earlier, Gen. Saleh’s units foiled a drug smuggling attempt when they seized a dhow transporting almost 253 kg of hashish and 186 kg of methamphetamine off the Hodeida coast. Drug trafficking still remains a key source of profit for Iran to fund the Houthi war effort. In early May 2025, the NRF thwarted two attempts to deliver military aid to the Houthis by blocking two Jalboot dhows en route from Djibouti to Ras Isa. The seized ships were laden with about 3 million detonators, 64 SATCOM devices, and 3,600 kilometers of detonating fuses. Notably, a reported thwarted Houthi UAV attack on a Yemeni Coast Guard (YCG) patrol boat near Zuqar Island on August 5 underscores the insurgent group’s steadfast resolve to disrupt counter-smuggling operations.

For Washington and its regional partners, pro-government interdictors present a valuable opportunity to enhance information-sharing and training. The CMF’s Task Force 150, Task Force 153 (Red Sea maritime security), and Task Force 154 (maritime security training), should deepen their operational coordination with Yemeni maritime units aligned with the PLC. Intelligence fusion, joint surveillance patrols, and real-time interdiction protocols can help close the gaps that smugglers currently exploit. Moreover, deploying U.S. maritime security advisors and enhancing radar and drone reconnaissance capabilities for Yemeni coastal units would significantly bolster their situational awareness effectiveness.

The European Union (EU) has a valuable role to play in this process. EUNAVFOR Operation Aspides, launched in February 2024 to safeguard commercial shipping in the Red Sea region, could expand its remit to include cooperative operations with Yemeni maritime forces. EU-led efforts in intelligence sharing, capacity-building, and legal interdiction training could support a layered maritime security framework that is both scalable and sustainable. The EU has already demonstrated operational agility and responsiveness, with its assets playing a crucial role in the salvage operation of the oil tanker MT Sounion and the rescue of seafarers from the vessel Eternity C. The EU’s experience in coordinating multilateral naval deployments in contested operational environments offers valuable lessons for effective coalition-building. In this regard, France appears to have taken an active lead, with military and political officers engaging in talks with the YCG on maritime security cooperation in Mocha and conducting a field visit to YCG units deployed in the Red Sea in late July.

The United Nations Office on Drugs and Crime (UNODC) could also be instrumental in further developing Yemen’s institutional capacity to manage interdiction. More precisely, the UNODC’s Global Maritime Crime Program (GMCP) has a proven track record in helping Yemen develop prosecutorial frameworks, port control standards, and vessel inspection protocols. Since 2018, the UNODC, through its GMCP Gulf of Aden and Red Sea team, has supported the rebuilding of the YCG with mentorship and training courses on critical maritime security competencies. In 2021, UNODC and the Yemeni government signed an MoU to strengthen cooperation on a container-monitoring program. More broadly, Yemen-UNDOC institutional engagement has expanded to include judicial reform and legislative capacity-building—efforts the two sides reaffirmed during a high-level meeting in May 2025 between Yemen’s Minister of Justice, Judge Badr al-Aredha, and UNODC Executive Director Ghada Waly. By strategically integrating UNODC into a broader approach to enhance the country’s maritime security capabilities, Yemeni forces could gradually move beyond ad hoc seizures toward a more institutionalized naval governance.

Ultimately, as the Houthis announced on July 27 the resumption of naval attacks against merchant vessels , stopping arms shipments before they reach combat zones is no longer just a short-term tactical advantage, but a strategic necessity. The July 16 seizure by Gen. Saleh’s forces offers a template for how this might be done: through enhanced local capabilities enabled by sustained international engagement. The recent operation serves as a reminder that maritime security in contested theaters is not solely the domain of the world’s most advanced navies. To prevail, these external actors must empower credible actors on the frontlines.

While the success of Saleh’s forces marks a positive development in curbing Houthi military supply lines, it also underscores the fragmented nature of Yemen’s anti-Houthi maritime forces. The complex patchwork of rival groups, overlapping jurisdictions, and divergent external backers has hindered the formation of national naval forces. In this context, international efforts to build local capacity must be carefully calibrated to foster interoperability and institutional cohesion, while avoiding the worsening of intra-Yemeni rivalries. A strategic approach to strengthen Yemen’s role as a maritime security actor in the Red Sea must balance operational effectiveness with political prudence to avoid reinforcing the very fault lines that continue to undermine the country’s long-term stability.

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the views of Gulf International Forum.