A man is being questioned by police after a meat cleaver attack during a row over two dogs.
A 39-year-old lost three fingers and had his left arm almost severed after arguing with two men about their dogs not being on leads.
The attack happened in Shepherds Bush, west London, on Tuesday night.
Police said a 23-year-old was arrested on Saturday and was being questioned over the incident which is being treated as attempted murder.
The injured man got into a row when two dogs started biting at his ankles.
He was pursued, the dogs were set on him and he was slashed with a meat cleaver.
The man managed get into the garden of a house and raise the alarm by banging on a window.