The court was shown CCTV footage of the killers stalking their target for much of the night before striking outside the Woody Grill kebab shop in Kilburn.
Sabrina Gachette, who sat in court with her mother throughout the trial, said:
Seeing that was scary. How many times did they see us but not once did I see them. They knew there was girls out there.
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Handyman Paul Thrower died after two 18-year-olds hacked at him with a 4ft long axe and stabbed him 10 times at a block of flats.
The 34-year-old victim was left with a huge gash across her nose and face. Police need to find a man seen on CCTV.
The girl was travelling on a train from London Liverpool Street to Romford in Essex after going to see the poppies at the Tower Of London.