Specifically, the UK-flagged Stena Impero was seized by Iran’s Revolutionary Guards in the Strait of Hormuz on July 16; In that occasion Iran stated that it seized the vessel for alleged marine violations, after the UK seized the Iranian Riah off Gibraltar.
The detentions spiked tensions in the area and the UK decided to lead in a new international maritime security mission, in collaboration with the US navy to assure the security of merchant vessels in the Strait of Hormuz.
In light of the mission, Vice Admiral Jerry Kyd, the Royal Navy’s Fleet Commander, during London Shipping International Week, quoted to Reuters that they had sent a few vessels and aircraft to the Strait because it has been a hot issue.
He continued that although the situation has been stable, the forces in the Strait remain alert.
We are there to assure the sanctity of international law and regulation and we will stay there, of course, for as long as we need
... commented Vice Adm. Kyd.
In addition, in early August CNN stated that vessels sailing in the Strait of Hormuz reported unusual GPS interference, among other problems, and the US believes Iran is to blame. In addition, Adm. Kyd confirmed that the vessels reported interference to their navigation systems.
'We are seeing much more state and non-state actors getting involved in things like GPS denial … to make navigation harder', he added.
- The background
The first incident that spiked the tensions, was in May, when the UAE said that four vessels were sabotaged at the Fujairah port.
In June, the shipping industry was present in an additional attack that took place in the Gulf of Oman against two vessels. The IMO Secretary General, the International Chamber of Shipping and INTERTANKO expressed their concerns, noting that this is an intolerable situation threatening the lives of seafarers, the environment and the world economy.
Despite these attacks, UK Royal Marines seized the Iranian 'Grace 1', near Gibraltar over suspected breach of EU sanctions earlier in July, and could only be released if the UK is guaranteed the oil is not bound for Syria.
Here you can see a timeline of the events that followed.