Somewhere in the Gulf of Oman in late April 2026, the crew of a bulk carrier approaching the Strait of Hormuz typed a new destination into their Automatic Identification System transponder. The port they entered was in China. The ship was not headed to China. The crew was gambling that Iranian fast-attack boats, which had already hit more than 20 commercial vessels since February, would think twice before striking a ship that appeared to belong to Beijing.
That gamble, documented through ship-tracking analysis of MarineTraffic transponder data reported by the Associated Press, captures how thoroughly Iran’s Islamic Revolutionary Guard Corps Navy has disrupted the world’s most important oil chokepoint. Since open hostilities between the United States and Iran began on February 28, 2026, small IRGCN speedboats have struck 26 commercial vessels transiting the Persian Gulf, the Strait of Hormuz, and the Gulf of Oman, according to data compiled by the United Kingdom Maritime Trade Operations center. The International Maritime Organization has independently confirmed the attack count and reported that seafarers have been killed and wounded in the strikes.
Despite the U.S. Navy’s overwhelming conventional superiority in the region, these fast-attack craft remain extraordinarily difficult to neutralize. They are too numerous, too shallow-drafted, and too quick to scatter before warships or aircraft can respond.
How the ‘mosquito fleet’ works
The IRGCN’s small-boat force has been central to Iranian naval doctrine for decades, but the current conflict has turned a theoretical threat into a daily operational reality. The fleet consists of dozens of fiberglass and aluminum speedboats, many no longer than 40 feet, armed with rockets, heavy machine guns, or improvised explosive charges. They operate from dispersed positions along Iran’s long Persian Gulf coastline, launching in clusters to swarm a target from multiple directions before peeling away.
Defense analysts have long called this a “mosquito fleet” strategy: no single boat poses a serious threat to a warship, but in groups of six, ten, or fifteen, they can overwhelm a merchant vessel’s ability to maneuver or call for help. Recent reporting by CNN detailed how this approach is now being applied at scale against commercial shipping, with attacks occurring multiple times per week during peak periods in March and April.
The boats’ shallow drafts let them operate in coastal waters where larger U.S. Navy vessels cannot safely follow. Their small radar signatures make them hard to track among the thousands of fishing dhows and pleasure craft that crowd the Gulf on any given day. And because they launch from civilian harbors, fishing villages, and camouflaged coastal positions, striking them preemptively would mean hitting targets ashore, a significant escalation that Washington has so far avoided.
Twenty-six ships, and crews still stranded
The 26-vessel figure rests on two institutional pillars. UKMTO, the Royal Navy-run tracking body that logs maritime security incidents across the Middle East, compiled the running tally. The IMO, the United Nations body responsible for maritime safety, separately verified the count in a press briefing that also confirmed seafarer casualties and the presence of stranded crews aboard vessels too damaged to move under their own power.
IMO Secretary-General Arsenio Dominguez condemned the violence in a formal statement that emphasized freedom of navigation and the protection of civilian shipping. In a subsequent briefing, he declared that “fragmented responses are no longer sufficient”, language that amounts to a public call for a coordinated multinational naval response. No specific coalition framework has been announced as of late May 2026.
The U.S. Maritime Administration’s advisory 2026-004 establishes the American government’s official threat assessment for the region. It specifies reporting mechanisms through NAVCENT, UKMTO, the National Response Center, and U.S. Coast Guard security directives, confirming that multiple allied agencies are actively tracking the threat. No declassified U.S. Navy incident reports have been released, so the attack count depends on UKMTO and IMO records rather than Pentagon data.
Ships are faking their identities to survive
The AIS-spoofing phenomenon is perhaps the most striking behavioral consequence of the campaign. AIS transponders broadcast a vessel’s identity, position, speed, and destination to other ships and to shore-based monitoring stations. Under international maritime law, commercial vessels are required to keep their AIS active and accurate. Falsifying that data is legally questionable and operationally dangerous, since it degrades the collision-avoidance system that every ship in a crowded waterway depends on.
Yet the AP’s analysis of MarineTraffic data found that multiple merchant ships approaching the Strait of Hormuz have altered their AIS destination fields to suggest Chinese affiliation, apparently calculating that Iranian forces will avoid provoking Beijing. The tactic reflects a grim arithmetic: naval escorts cannot be everywhere at once, and a deceptive transponder signal may offer better odds than waiting for a warship that is protecting another convoy miles away.
The full scope of identity manipulation is hard to measure precisely because the practice is, by design, meant to avoid detection. But the fact that it is happening at all signals how deeply the speedboat campaign has eroded confidence in conventional naval protection.
The economic shockwave beyond the strait
The Strait of Hormuz handles roughly 20 percent of the world’s petroleum supply on any given day, according to the U.S. Energy Information Administration. When ships reroute, delay transits, or cancel voyages altogether, the effects cascade through energy markets, freight rates, and marine insurance premiums.
Insurance underwriters have raised war-risk premiums for Hormuz transits since the conflict began, though precise figures have not been publicly disclosed by the major syndicates. Some cargo is being rerouted around the Cape of Good Hope, adding weeks and significant fuel costs to voyages that would normally pass through the Gulf. Shipping companies have reported delays and diversions, but comprehensive statistics on lost tonnage or added voyage days have not been released as of late May 2026.
The mosquito fleet does not need to sink supertankers to achieve strategic effect. It only needs to make the passage dangerous enough that the commercial world starts pricing in the risk. Every percentage-point increase in insurance premiums, every rerouted cargo, and every delayed loading eventually reaches consumers at fuel pumps and in the price of imported goods.
What remains unclear
Several important questions lack definitive answers. The exact number of IRGCN speedboats, their precise basing locations, and the fleet’s total operational capacity are drawn from analyst estimates rather than verified intelligence disclosures. Without that granularity, outside assessments of how many boats Iran can deploy at any given time vary widely.
Whether Iran is deliberately calibrating the intensity of attacks to stay below a threshold that would trigger a broader U.S. military response is a matter of interpretation. Some analysts read the pattern as strategic restraint designed to maximize pressure on maritime traffic without inviting overwhelming retaliation. Others see it as a reflection of the fleet’s limited firepower and fragmented command structure rather than a deliberate choice. Without access to internal Iranian decision-making, neither reading can be confirmed.
The names of the 26 struck vessels, the nationalities of the killed and injured seafarers, and the specific cargoes affected have not been fully disclosed by UKMTO or the IMO. That absence makes it difficult to assess whether Iran is targeting ships selectively, perhaps avoiding certain flag states, or striking opportunistically at whatever enters range.
A low-tech threat with high-stakes consequences
What the institutional record confirms is striking in its simplicity. Small fiberglass boats, operating close to shore with limited armament, have forced some of the world’s largest shipping companies to alter routes, falsify transponder data, and factor new layers of danger into voyages that were routine six months ago. The IMO’s call for a coordinated multinational response suggests that the current patchwork of national naval patrols and advisories is not keeping pace with the threat.
For the crews still stranded aboard damaged ships in the Gulf of Oman, the policy debate is academic. They are waiting for tugs, for salvage teams, or simply for the fighting to stop. The mosquito fleet that put them there will keep launching as long as Iran has coastline, fuel, and speedboats to spare. And as of late May 2026, it has plenty of all three.
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*This article was researched with the help of AI, with human editors creating the final content.
