LONDON (Reuters) - British police are keeping an open mind on whether more than one person was responsible for a London train bombing that injured 30 people, after they arrested an 18-year-old man earlier on Saturday.  We are still pursuing numerous lines of enquiry, and at great pace,   Senior National Co-ordinator for Counter Terrorism Policing Neil Basu told reporters.   Our priorities are ... to identify and locate any other potential suspects.   
UK police keeping open mind on number of suspects in London train bombing