AFP - Iranian Nobel peace prizewinner Shirin Ebadi called Tuesday for the release of five Britons seized in Gulf waters, saying they were arrested without warning.

"I believe the Iranian government has arrested them without warnings. They must be released as soon as possible," she told reporters in Seoul.

The five were sailing from Bahrain to the start of a race in Dubai when their yacht was stopped last Wednesday in the Gulf, the British Foreign Office said.

The yacht may have been drifted into Iranian waters after breaking its propeller en route to the Dubai-Muscat Offshore Sailing Race, which started last Thursday, British media reports said.

Ebadi, a lawyer and human rights defender who won Nobel peace prize in 2003, said the Britons might have entered Iranian waters by mistake.

"In this case, (Iranian) maritime police should have escorted them out into international waters," she said through an interpreter.

A top aide to Iran's President Mahmoud Ahmadinejad on Tuesday confirmed the detention of the five Britons and vowed they would be dealt with "firmly" if found guilty.