April 29, 2026: Iran War Maritime Intelligence Daily

At a Glance

• Hormuz transit holds at 13 crossings, all AIS-visible with no dark activity.
• Gulf vessel presence declines to 890, indicating a slight contraction.
• Dark activity rises sharply to 148 events, signaling increased deception.
• Chabahar cluster expands with five dark tankers holding 7–8M barrels capacity.
• Iranian-linked vessels intensify AIS spoofing to mask crude loading.
• The system reflects visible transit alongside growing concealment and evasion.

Operational Overview 

Maritime activity across the Strait of Hormuz remains stable in volume but increasingly uneven in behavior, with full AIS visibility during transit contrasted by a sharp rise in deceptive activity across the broader Gulf.

On April 28, transit volumes held steady, with all crossings conducted while transmitting AIS. At the same time, Gulf-wide vessel presence declined slightly, while dark activity increased significantly, indicating renewed reliance on deceptive shipping practices despite visible transit compliance.

East of Hormuz, dark tanker positioning near Chabahar continues to build, reinforcing the role of Iranian territorial waters as a holding and staging area under sustained enforcement pressure.

Across the system, vessel behavior reflects a deliberate split between compliance and evasion. Transit through the Strait remains fully visible and controlled, while deceptive activity is expanding across the wider Gulf. This indicates a shift in how risk is managed, with operators maintaining compliant passage through chokepoints while relocating higher-risk behavior into less visible zones.

Transit Holds with Full Visibility

Transit activity through the Strait of Hormuz remained steady on April 28, maintaining moderate volumes under full transparency.

A total of 13 vessels crossed the Strait, including 4 inbound and 9 outbound transits. All movements were AIS-visible, with no dark transits recorded.

Inbound traffic included one Panama-flagged bulk carrier and three cargo vessels, one flagged to Comoros and two to India. Outbound traffic consisted of two tankers flagged to Panama, two bulk carriers flagged to Panama and China, and five cargo vessels, with one flagged to Antigua and Barbuda, two to Iran, and two to Comoros.

All transits were routed through the Northern Corridor.

A notable movement included a Japanese-owned, Panama-flagged VLCC transiting outbound without Iranian linkage, reinforcing that non-sanctioned commercial traffic continues to move through the Strait under current conditions, even as Iran-linked activity remains constrained.

Gulf Activity Contracts as Deception Surges

Total vessel presence across the Gulf declined slightly to 890 vessels, continuing the gradual contraction seen in recent days.

Panama remains the dominant flag state with 142 vessels, followed by Iran (93), Comoros (83), the UAE (74), Marshall Islands (72), and Liberia (67).

Fleet composition includes 144 bulk carriers, 136 product tankers, 79 crude tankers, 64 container ships, 40 LNG and LPG carriers, and 33 chemical tankers.

In contrast to the modest decline in vessel count, dark activity surged to 148 events, marking a significant increase compared to the previous day.

This divergence points to a clear shift in behavior. While overall traffic is easing, vessels are increasing reliance on concealment and deceptive shipping practices, adjusting to sustained enforcement pressure rather than reducing activity outright.

Chabahar Cluster Expands Under Dark Conditions

Dark tanker positioning east of Hormuz continues to consolidate near Chabahar, reinforcing its role as a staging zone outside the primary enforcement area.

Windward Multi-Source Intelligence identified five dark tankers in the Chabahar port waiting area on April 28. One vessel was identified with high confidence as an Iranian-flagged VLCC, DIONA (IMO 9569695), assessed to have arrived from the Singapore/Malaysia ship-to-ship transfer hub, a known center for Iranian crude consolidation and redistribution.

Two AIS-transmitting Iranian-flagged vessels, the container ship KASHAN (IMO 9270696) and the bulk carrier ARTMAN (IMO 9405930), were also detected operating in proximity to the dark cluster.

The five dark tankers represent an estimated 7–8 million barrels of carrying capacity. Their positioning within Iranian territorial waters indicates deliberate staging, with vessels likely either laden and awaiting offload or in ballast awaiting loading instructions, while remaining shielded from enforcement exposure.

ARTMAN’s trading pattern, including voyages between Iran and China, aligns with profiles seen in previously intercepted vessels, reinforcing its relevance within the broader Iranian shipping network.

Blockade Impact on Dark Vessel Behavior

Dark vessel positioning around Bandar Abbas and the Larak Island chokepoint provides a clearer view of how the blockade is shaping movement patterns.

At Bandar Abbas, dark vessel concentration remains elevated. Multi-source detection shows a dense cluster of tankers and bulkers anchored in the deepwater channel between the mainland (Bandar Abbas / Shahid Rajaee) and Qeshm Island. Additional clusters are positioned along the Qeshm shoreline, with a thinner spread extending east toward the Strait of Hormuz.

This spatial pattern is consistent across multiple collections and reflects sustained loitering rather than active transit. The area continues to function as a dual-use anchorage, supporting both commercial staging and IRGC-N co-located activity under constrained conditions.

At the Larak Island chokepoint, the pattern is notably different. Dark vessel detections form a narrow north–south ribbon hugging the Iranian coastline, particularly along Bandar-e Charak and the western shore of Larak Island. There is minimal presence in open deep water.

Between April 22 and April 27, a measurable decrease in dark vessel movement was observed at this chokepoint. This suggests reduced transit of non-AIS vessels into and out of the Arabian Gulf.

The reduction aligns with the effects of the U.S. blockade. While vessels continue to stage and cluster within Iranian-controlled waters, fewer are attempting dark transit through the chokepoint itself.

Taken together, the pattern indicates a shift from movement to containment. Dark vessels are still present at scale, but are increasingly concentrated in controlled anchorage zones rather than actively transiting, reflecting the growing impact of enforcement on routing decisions.

Deceptive Shipping Practices Intensify

Deceptive shipping practices are escalating, with 10 Iran-trading, U.S.-sanctioned tankers actively spoofing their locations to appear anchored off Basrah, Iraq.

This reflects a long-established evasion tactic. Tankers manipulate AIS signals and transmit false voyage data indicating Iraqi destinations, often supported by fake ownership messages. In practice, these vessels divert to Iranian ports to load sanctioned crude, while AIS data shows them arriving at Iraq and later departing laden, creating the appearance of compliant trade.

This activity is now under intensified scrutiny as the U.S. embargo on Iranian ports tightens.

The vessels identified include four VLCCs — ALICIA (IMO 9281695) and RHN (IMO 9208215), both operating under fraudulent Curacao registries, STAR FOREST (IMO 9237632) flagged to Hong Kong, and AQUA (IMO 9248473) under a fraudulent Malawi registry.

Additional vessels include the Hong Kong-flagged handysize tanker PAOLA (IMO 9299458) and the LR1 tanker ADENA (IMO 9254862), both signaling “Iraqi owner,” linked to a network identified by the U.S. Treasury as facilitating Iranian oil sales.

Three medium-range tankers — AQUALIS (IMO 9258674) under a fraudulent Guyana registry, KUSH (IMO 9282522) falsely flagged to Comoros and signaling destination “KAZ” (Khor Al Zubair), and CHARMINAR (IMO 9318022), also falsely flagged to Comoros — are part of the same pattern. CHARMINAR is linked to a known Iranian trading network.

The LPG carrier ROYAL H (IMO 9155341), flagged under a fraudulent Malawi registry and recently sanctioned, is also engaged in this activity.

Most vessels display clear spoofing indicators, including repeated positional patterns and erratic AIS trails. 

In the case of ROYAL H, voyage data simulates loading at the Iraqi LPG port of Khor Al Zubair, a known tactic among Iran-linked LPG carriers.

These tankers are part of a broader group of Iran-trading vessels now largely confined west of Hormuz under blockade pressure. Together, they illustrate how deceptive shipping practices remain central to sustaining Iranian export flows, even as enforcement tightens and physical movement becomes more constrained.

Outlook

Transit through the Strait remains stable and fully visible, with consistent volumes and no dark crossings, reinforcing that chokepoint movement continues under controlled conditions.

At the same time, risk is no longer concentrated within the Strait itself. As enforcement pressure persists, vessel behavior is shifting outward, with increased reliance on concealment, spoofing, and staging in peripheral areas such as Chabahar and Bandar Abbas.

This indicates a transition from disruption to adaptation. Movement is not stopping, but being redistributed, with compliant transit maintained where visibility is highest and evasive activity pushed into areas where monitoring is more limited.

The operating environment is increasingly defined by this separation, where visibility does not equate to transparency, and reduced friction at chokepoints masks growing complexity across the wider system.