Moments before Mrs Silva was attacked yesterday, a man was seen killing a cat and attacking a woman, smashing her car window as she cowered inside it.
Armed police officers raced to the scene in Nightingale Road, Edmonton, and ran through the street shouting at people to run for their lives.
Children screamed as police used battering rams and metal batons to smash windows and doors before dragging them to safety.
More than 20 officers were involved in arresting the man, who was shot with a Taser in a desperate bid to subdue him.
One officer broke their wrist in the chaos and a senior officer said police ‘put their lives on the line’ to stop the attack.
At some point, the knifeman targeted a grey Ford Focus carrying a man and a woman and struck the vehicle as they tried to escape.
"In a time of universal deceit, telling the truth is a revolutionary act." - George Orwell