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LONDON - Police arrested three men today in connection with the July 7, 2005, suicide bomb attacks that killed 52 commuters on London's transport system.
The men were arrested by counter-terrorism police "on suspicion of the commission, preparation, or instigation of acts of terrorism" in the north of England, a police statement said.
Two were arrested at Manchester airport where they were due to fly to Pakistan. The third was arrested in a house in Leeds, the northern city which was home to three of the suicide bombers.
The suspects were taken to a central London police station to be questioned. Searches were underway at five houses in the Leeds area and two premises in east London, the police said.
No one has yet been charged in connection with the attacks, in which all four bombers died.
The head of London's anti-terrorist branch said last year police were chasing several leads in Britain and abroad in an attempt to find anyone involved in the planning of the attacks.
The government has said that the four bombers were probably led by Mohammad Sidique Khan, the oldest of the group.
Two of the bombers had attended training camps in Pakistan and they were suspected of having links to militants there.
Terrorism experts say attacks are often coordinated by a handler or a planner, and it was very unlikely that a group of self-starting militants operating without any backing would be successful.
They also say the explosives believed to have been used would have required an experienced bomb-maker.
- REUTERS