Air defences were activated in Tehran on Thursday and explosions were reported in the southern Iranian cities of Bandar Abbas and Minab, according to the state-linked Mehr news agency, in a fast-moving development near the Strait of Hormuz whose cause was not immediately clear.
Mehr said another explosion had been heard in Bandar Abbas and that a blast was also heard in Minab, a city east of the port. Both locations are north of the Strait of Hormuz, one of the world’s most important oil shipping routes.
Fars News, which is affiliated with Iran’s Revolutionary Guards, also reported that residents had heard multiple explosion-like sounds in Bandar Abbas, but said the source was unclear. Iranian authorities had not immediately issued a fuller explanation, and there were no confirmed reports of casualties or damage. The reports could not be independently verified.
The activation of air defences in the capital raised the possibility of an attempted interception, a suspected drone or missile threat, or a precautionary military response during operations elsewhere in the country. By late Thursday, however, Iranian officials had not publicly said why the systems had been activated.
The reports come amid a broader escalation in and around the Gulf, where shipping lanes, naval facilities and regional airspace have all come under increasing pressure in recent days. Bandar Abbas is Iran’s principal naval and commercial port and hosts key military and port infrastructure, giving any reported incident there immediate strategic significance. Minab lies further east in Hormozgan province, near sensitive approaches to the strait.
The area has already featured prominently in the current conflict. Earlier this year, Bandar Abbas was the subject of repeated reports of strikes and military activity affecting naval zones and port facilities. Thursday’s reports therefore risk being seen as part of a wider pattern rather than an isolated local incident, although that had not been established.
The latest developments follow a sharp rise in maritime confrontation in the Strait of Hormuz. On 4 May, the US military said it had sunk six Iranian boats that it said were targeting civilian vessels and had escorted US-flagged ships through the strait. The UAE has also said it was attacked by missiles and drones during renewed hostilities.
On 5 May, the UK Maritime Trade Operations organisation said a cargo vessel in the strait had been struck by an unknown projectile. South Korea separately reported an explosion aboard a merchant ship in the same waterway, though the cause was not immediately clear.
Any sign of military activity around Bandar Abbas is likely to be closely watched by shipping and energy markets. About 20 per cent of global oil trade passes through the Strait of Hormuz, and the latest crisis has already pushed up insurance costs and disrupted tanker movements, according to European and maritime reporting in recent days.
The developments are also likely to be followed closely in London. The UK government said in March that it had authorised the United States to use British bases for what it described as “specific and limited defensive operations” aimed at degrading missile sites used to attack shipping in the strait. Britain also said it had reinforced Gulf air defences by deploying additional systems to Bahrain.
France, meanwhile, has been moving its carrier strike group closer to the wider theatre as Western governments weigh further steps to protect commercial shipping. British ministers have previously pushed for a broader political coalition to help secure the strait.
The UK government has framed the confrontation with Iran as both an overseas military issue and a domestic security concern. In a statement in February, the Prime Minister said Iran had backed 20 potentially lethal threats on UK soil in the previous year, while ministers later published a legal justification for defensive military action if it was considered necessary and proportionate.
For now, the immediate questions remain unanswered. It is not yet clear whether the explosions in Bandar Abbas and Minab were caused by external strikes, air defence interceptions, military detonations or an industrial incident. It is also unclear whether the activation of air defences in Tehran was directly linked to the blasts in southern Iran.
Further clarity is likely to depend on statements from Iranian officials, military briefings from the US and allied governments, shipping advisories and any satellite imagery that emerges from the affected areas.
This is a developing story.