In a statement he says:
"The Metropolitan Police have confirmed that the explosion on a train at Parsons Green Station this morning is being treated as terrorism.
Our city utterly condemns the hideous individuals who attempt to use terror to harm us and destroy our way of life.
As London has proven again and again, we will never be intimidated or defeated by terrorism.
I am in close contact with the Metropolitan Police, Transport for London, Government and other emergency services who are responding at the scene and leading the investigation. I will be attending the emergency COBRA meeting in Whitehall this afternoon with the Prime Minister.
My sincere gratitude goes to all our courageous emergency responders and the TfL staff who were first on the scene.
I urge all Londoners to remain calm and vigilant, and to check TfL’s website for travel advice."
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