Kevin Nugent's dog Orlando was attacked in Wembley last May by a 'dangerous' dog. The owner of the attacking dog carried on walking and disappeared. Orlando was rushed to the vets where they found eight severe puncture wounds to his neck.
Under new government proposals, owners of dangerous dogs could face life in prison.
More top news
The 47-year-old man died shortly after 3pm on Tuesday.
Specialist explosive detection dogs searched through the town examining letter boxes and phone booths for signs of potential devices.
Temperatures reached 29.1C in St James's Park, central London.