A man arrested after a stabbing frenzy at a London supermarket had been released on bail earlier that morning after being charged with possessing a knife.
Four women suffered knife wounds during a bloody attack at around 10.35am on Friday outside a Sainsbury's supermarket in Hampton, west London.
A 66-year-old man has been arrested and remains in custody.
Police, who have informed the Independent Police Complaints Commission (IPCC) about the incident, said the man had been arrested in connection with a separate incident on Thursday in Kensington High Street.
He was charged with possessing a knife and assaulting a police officer and released on bail on Friday morning ahead of a court date next month.
Following the attack in Hampton, a 62-year-old woman is fighting for her life while a 53-year-old victim who was transferred to hospital by air ambulance is now stable.
The other two women, aged 67 and 71, are in hospital with non-life threatening injuries.
Police do not believe the attack to be terror-related.
Witnesses described seeing a man with a knife and images from the scene showed bloodstained clothes lying on the ground.
Ben Brady, 30, who owns Jen's Salon next door to where one of the victims was treated, said the man was "waving a knife" then attacking women as they got out of their cars.
The first victim was stabbed near the pub before the attacker moved on to another area of the car park, he said.
"She had no idea what was going on," he added.
A member of staff at the nearby Hampton pub said the man "appeared to be out of it" and was only targeting women.
"The man ran through and started attacking them. It didn't seem like they knew him. It was completely unprovoked," the woman, who did not want to be named, said.
"He appeared to be out of it, on drugs or crazy.
"The woman who was badly stabbed in the back made it up to the police station and raised the alarm.
"She is well-known locally and always goes shopping there all the time."
Police praised those who helped the victims, saying they had shown "outstanding courage", and reassured locals officers are on patrol in the area.
The Directorate of Professional Standards has informed the IPCC about the incident.
Chief Superintendent Glenn Tunstall, borough commander for Richmond-Upon-Thames, said: "I would like to praise members of the public who rushed to the aid of the injured women and provided them with first aid.
"Their bravery and the outstanding courage of the officers who were first on the scene and confronted the armed man is worthy of praise.
"An incident like this will cause considerable concern to the local community, and I would like to reassure them that uniform officers will be patrolling the area and can speak to anyone who has concerns."
One of the victims went to a police office, less than 100 yards from the car park, where she was treated.
A blood-soaked jacket and first aid kit were seen lying on the ground surrounded by police tape outside the Hampton and Hampton North Wards police office.
The car park by the Sainsbury's store backs on to a pub, youth centre, children's hospice and school.