Iranian drone attack on tanker Mercer Street off Oman kills two crew members
Incident Report
Fact Sheet
| Date | 30 Jul 2021 |
| Tracker | Strait of Hormuz Tensions |
| Type | Strike |
| Location |
Gulf of Oman
25.12, 56.33 (approximate) |
What Happened
On July 29-30, 2021, the Liberian-flagged, Japanese-owned tanker Mercer Street came under a series of one-way drone attacks while transiting international waters off Masirah Island, Oman. Two drones missed on the evening of July 29; a third struck the vessel's pilot house on July 30, killing the ship's master, a Romanian national, and a security officer, a UK national. US Central Command's forensic investigation attributed the strike to Iran, matching drone debris to prior Iranian one-way attack UAVs. Iran denied involvement; the US, UK and Israel condemned the attack.
Sources
Measured Footprint
| Series | That day | Prior 30-day avg | Week after vs before |
|---|---|---|---|
| Transits | 83 +1% | 81.8 | +4% (586 → 608) |
| Tankers | 50 -3% | 51.7 | +2% (372 → 380) |
| Cargo ships | 33 +10% | 30.1 | +7% (214 → 228) |
Daily figures from IMF PortWatch around July 30, 2021; the day's value is compared with the trailing 30-day average. Week comparisons are shown only when the series covers both full weeks.
Gulf of Oman
Marker placed at sea area precision.
Activity Around the Incident
Commercial ship transits of the Strait of Hormuz, two weeks either side
Daily counts from IMF PortWatch; the highlighted bar is the incident day, July 30, 2021.
Incidents Around the Same Period
Nearest logged incidents
| Date | Type | Incident |
|---|---|---|
| 4 Jan 2021 | Interception | Iran seizes South Korean tanker Hankuk Chemi near the Strait of Hormuz |
| 3 Aug 2021 | Interception | Armed boarders briefly seize tanker Asphalt Princess off UAE in foiled hijacking |
| 27 May 2022 | Interception | Iran seizes two Greek-flagged tankers, Prudent Warrior and Delta Poseidon, in the Persian Gulf |
| 27 Apr 2023 | Interception | Iran seizes two tankers, Advantage Sweet and Niovi, within a week in the Strait of Hormuz area |