Live updates: 'No evidence' stabbing suspect was radicalised
- The US woman stabbed to death in Russell Square has been named as Darlene Horton
- Five other people were injured in the attack which happened late on Wednesday
- A 19-year-old Norwegian man is being held on suspicion of murder
- Police do not believe he was "in any way motivated by terrorism"
- Those injured are Australian, American, Israeli and British
- The Metropolitan Police commissioner has vowed to "protect our capital"