The incident happened near the level crossing this morning (credit: Google Maps)
It happened in Larkshall Road, near Highams Park, in the early hours of this morning.
The 18-year-old is being treated in hospital.
Detective Inspector Daniel Thompson, leading the investigation said: “A young man is currently in hospital fighting for his life as a result of this attack. We are just a few hours into our investigation we really need to speak to anyone who was in the area at the time and witnessed any suspicious activity around the railway crossing on Jubilee Avenue.
“I am especially keen to hear from anyone who saw a silver car that was paying particular attention to this incident. We know that this car stayed in the area for a number of minutes before driving away in the direction of Broadway.”
The car is “possibly a Volkswagen Golf”, according to police.
An 18-year-old man has been arrested on suspicion of affray and is currently in police custody.
If you have any information that could help the investigation please call police on 101 and quote CAD 661/18August.
Alternatively, if you want to remain 100% anonymous contact Crimestoppers on 0800 555 111.
They are a totally independent charity, they never ask your name and they cannot trace your call, your IP address, or device you use. Alternatively, visit their website.
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Tags: Chingford, Waltham Forest, Highams Park