These harrowing images show the "police tape and blood stains" left in a busy South Harrow road following a vicious late-night assault .
There, officers found a 53-year-old man suffering from serious head injuries. He has been taken to hospital.
It has been confirmed a suspect was arrested at the scene on suspicion of causing grievous bodily harm.
According to the Met, investigations were ongoing at the scene into daylight hours on Saturday when a forensic team arrived to analyse blood stains in the road.
Now, pictures taken by a passer-by show the bloody aftermath of the incident clearly visible in the road.
Members of the public took to Twitter on Saturday morning to describe what they had witnessed at the scene.
Kuha Kumaran said: "Yet another crime scene on Northolt Road in South Harrow station. Why can't Harrow council install CCTV and send a tough message?"
Another added: "Same place in South Harrow, police tape and blood stains."
The Met spokesman added on Sunday morning (October 15) the force is still awaiting an update on the man's condition.
Anyone with information is asked to call the Metropolitan Police on 101 or call Crimestoppers charity anonymously on 0800 555 111.
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