Iran says it has seized eight British sailors and three naval vessels that allegedly strayed into Iranian waters near Iraq.
British military spokesmen say communication was lost early Monday with three small Royal Navy patrols boats and eight crewmen in the Shatt al-Arab waterway that divides Iraq and Iran.
A spokesman in Baghdad for the U.S.-led coalition in Iraq, Brigadier General Mark Kimmitt, says the British boats were conducting a training exercise.
"This morning at about 0500 [0100 UTC], three boats, eight persons, from the Royal Naval training team operating out of Basra departed on a mission for training with their fellows in the Iraqi navy," he said. "We don't have much more than that."
The British have provided coastal defense training to the Iraqi navy for the past several weeks in the waters off the southern coast.
An Iranian foreign ministry spokesman says the crew was being interrogated and an investigation was under way. An Iranian government television station said weapons, maps and other military items were seized.
British diplomats have been in touch with their Iranian counterparts in London and Tehran.
The incident comes amid new strains in relations between the two countries after Britain criticized Iran last week for not cooperating sufficiently with international inspections of its nuclear program.