07:09

A Norwegian national of Somali origin has been arrested on suspicion of murdering an American woman and injuring five others, including Britons, in what was described by police as a “spontaneous attack”.

Speaking outside Scotland Yard headquarters, Metropolitan police assistant commissioner, Mark Rowley, said there was no evidence that the 19-year-old suspect had been radicalised.

While the investigation is not yet complete all of the work we have done so far, increasingly points to this tragic incident as having been triggered by mental health issues. Indeed at this time we believe it was a spontaneous attack and the victims were selected at random.

Rowley said officers had interviewed the suspect and his family, and had searched addresses.

The woman murdered was an American national, Rowley said, those injured were Australian, American, Israeli and British.