Police have released shocking CCTV images of a mugger repeatedly punching a teenage girl as a passer-by fails to even look up from his mobile phone.
Alex Tree, 18, was attacked as she walked through an underpass in Walthamstow, north-east London, on her way to visit her grandmother.
As she was walking under the roundabout at 2pm on Saturday, a man on a bicycle approached her and demanded she hand over the bags she was carrying from JD Sports and CeX.
Alex, who is autistic, told him to go away but he knocked her to the ground and punched her a number of times in the head - causing her to bleed heavily from the ear - before taking a spanner out of his pocket and threatening to hit her.
He then wrenched her bag off her and cycled away. She suffered bruising and a burn to her neck, where the attacker ripped the bag from her.
However, as the robbery was happening another man walked past the attacker and victim but did nothing. He was either unaware or chose to ignore what was happening - and instead concentrated on his phone.
Alex said a couple with a pram also watched the attack without intervening. Alex said: "This guy was just standing there watching while he just kept punching and punching me. They didn't want to get involved in case they got hurt but I was on my own."