"We can confirm we have detained some persons who we suspect may have information that would be helpful to our inquiry," a spokeswoman said: "They will be detained in accordance with the Geneva Convention."

Prime Minister Tony Blair caused a storm on March 27 when he said that the men had been executed by Iraqi forces. The sister of one of the victims branded him a liar, telling a British newspaper that, according to the defence ministry, the men had died in combat.

Bomb disposal experts Luke Allsopp, 24, of London, and Simon Cullingworth, 36, from Essex, east of London, went missing on March 23 after an attack on military vehicles near Al Zubayr.

Their bodies were later shown on Qatar-based satellite broadcaster Al-Jazeera, prompting international condemnation.

"We can't confirm that our personnel have been executed," the defence ministry spokeswoman said.

"We are seeking information from the Iraqi people regarding the location of the bodies of our missing personnel and are actively trying to establish the circumstances of their deaths," she said.

The announcement came after two men, reported to be father and son, were stopped earlier Friday at a road block set up by British troops at Al Zubayr, 15 miles (24 kilometres) outside Basra.

Earlier, the defence ministry confirmed one man had been arrested. He was named in reports as Khalid Barour, the reported father and a senior official in President Saddam Hussein's Baath Party.

WAR.WIRE