UK police hunt 'master bomber'

Anti-terrorist police have said it would be "remarkably reckless" to rule out further attacks in Britain -- despite Tuesday's stunning breakthrough in the bid to track down those who carried out the killings.

The police investigation is expected to focus on the towns and cities of West Yorkshire, in northern England, where three of the four bombers are known to have lived.

The region has a big Muslim population, and police will try to establish whether it is harboring a cell or an operative, possibly from al Qaeda, who might have planned the bombings which killed at least 52 people and injured 700.

Media reports suggest the four bombers were aged between 19 and 30 and were so-called "cleanskins" -- with no convictions or known terror involvement.

The suspects were all believed to be British nationals, of ethnic Pakistani origin.

A series of papers named two of the dead suspected bombers as Hasib Hussein, 19, and 22-year-old Shehzad Tanweer, who lived in Leeds.

The Daily Mail said that Hussein carried the bomb that exploded on a packed double-decker bus in central London, while Tanweer detonated a device on the London Underground near Edgeware Road station, to the west of the city.

The paper named 30-year-old father of one Mohammed Sadique Khan, also from Leeds, as having been responsible for another subway blast near Aldgate station, just east of the city centre.

Meanwhile British Prime Minister Tony Blair on Wednesday urged Britons to react calmly to last week's London bombings and condemned attacks against Muslims.

"I would ask for the same measured and calm response from the country that has characterised it since last Thursday," when bombers struck at the city's transport system, killing more than 50 people, Blair told parliament.