On 23 March 2007, fifteen Royal Navy personnel from HMS Cornwall were searching a merchant vessel when they were surrounded by the Navy of the Iranian Revolutionary Guards and detained off the Iran–Iraq coast. In the course of events, British forces claimed that the vessel was in Iraqi waters, but the Iranians insisted that they were in Iran's territorial waters. The fifteen personnel were released thirteen days later on 4 April 2007.

HMS Cornwall was a Batch 3 Type 22 frigate of the Royal Navy. She was the first Batch 3 to be built, and the last to decommissioned. Cornwall was based at HMNB Devonport in Devon, England, part of the Devonport Flotilla.