Explosions in London’s subway

A British police officer joins mourners outside King’s Cross Station in London.  (Scott Barbour / Getty Images)

The four bombers are believed to have traveled together from the north, then split up for the attacks.  (John Giles / AP)

Residents of a home in Leeds, north of London, speak to police. Officials believe one of the bombers may have helped recruit and prepare fellow Pakistani-Britons in the town.  (John Giles / AP)

British police and forensic officers in Leeds take part in the search of one of six houses raided in connection with last week’s attacks in London.  (Paul Barker / AFP/Getty Images)

UNDER SCRUTINY: A policeman stands guard in Leeds, England, where neighborhoods were raided by authorities investigating last week’s deadly bombings in London. The Yorkshire region has seen substantial activity by Islamic extremists.  (Matthew Roberts / Getty Images)

A police forensic officer looks for evidence on the grounds of St. Pancras Parish Church near the scene of the double-decker bus bombing in Tavistock Square.  (Peter MacDiarmid / Getty Images)

HIGH ALERT: Police patrol in London a day after the attacks. Crews were still trying to recover the bodies in one subway train.  (Sang Tan / AP)

London police officers guide traffic away from Ray’s Inn Road and the King’s Cross underground station.  (Annie Wells / LAT)

A British Transport Policeman, who declined to give his name, guards an entrance to the King’s Cross subway.  (Annie Wells / LAT)

At the entrance to King’s Cross underground station, a German traveler, who declined to give his name, studies a London map to try to figure out how to get to Heathrow Airport. On the left, an underground security guard passes by.  (Annie Wells / LAT)

BACK IN BUSINESS: Derek Knight sells papers at a newsstand at King’s Cross Station today, though the station remained closed to Underground service the day after the blast nearby.  (Annie Wells / LAT)

Emergency services outside King’s Cross station in London.  (Photo by Dean Mouhtaropoulos/Getty Images)