The British government demanded “the immediate and safe return of our people and equipment.”
The British Navy personnel were “engaged in routine boarding operations of merchant shipping in Iraqi territorial waters,” and had completed a ship inspection when they were accosted by Iranian vessels, Britain's Defense Ministry said.
“We are urgently pursuing this matter with the Iranian authorities at the highest level and ... the Iranian ambassador has been summoned to the Foreign Office,” the ministry said.
The seizure comes at a time of rising tensions between Iran and the West, which accuses the Islamic republic of violating a U.N. calls for it to halt uranium enrichment and open its nuclear program for inspection. It also comes amid U.S. accusations that Iran is funding and arming Shiite militias in Iraq, worsening sectarian tensions there.
The United States, Britain's chief ally, has built up its naval forces in the Gulf in a show of strength directed at Iran. Two American carriers, including the USS John C. Stennis - backed by a strike group with more than 6,500 sailors and Marines and with additional minesweeping ships - arrived in the region in recent months, ratcheting up tensions with Iran.
A Pentagon official said the Britons were in two inflatable boats from the frigate H.M.S. Cornwall during a routine smuggling investigation, said the official, who spoke on condition on anonymity because he was not authorized to speak about the incident.
He said the confrontation happened as the British contingent was traveling along the boundary of territorial waters between Iran and Iraq. They were detained by the Revolutionary Guard's navy after inspecting a merchant ship believed to be smuggling cars, he said.
A fisherman who said he was with a group of Iraqis from the southern city of Basra fishing in Iraqi waters in the northern area of the Gulf said he saw the Iranian seizure. The fisherman declined to be identified because of security concerns.
“Two boats, each with a crew of six to eight multinational forces, were searching Iraqi and Iranian boats Friday morning in Ras al-Beesha area in the northern entrance of the Arab Gulf, but big Iranian boats came and took the two boats with their crews to the Iranian waters.”
In June 2004, six British marines and two sailors were seized by Iran in the Shatt al-Arab between Iran and Iraq. They were presented blindfolded on Iranian television and admitted entering Iranian waters illegally, then released unharmed after three days.