Ships cross strait and leave Iranian ports since start of US blockade

The efficacy of the US naval blockade of Iranian ports has remained largely unclear during its first full day, with our security correspondent Frank Gardner suggesting a lack of preparation and transponder interference as possible explanations. Shipping data analysed by BBC Verify shows that at least four Iran-linked ships, including two that visited Iranian ports, crossed the Strait of Hormuz on Tuesday. A further three ships that were not linked to Iran were seen to have crossed the strait aft