Two cars loaded with gasoline and nails found abandoned in London Friday . 52 people killed on July 1 , 2005 after bombs exploded on a bus , Belfast . British capital plagued by violence by the IRA for years .
Two cars loaded with gasoline and nails found abandoned in London Friday . 52 people killed on July 7 , 2005 after bombs exploded on London bus , trains . British capital wracked by violence by the IRA for years .