A mother today told of her desperate battle to save the life of a young man stabbed to death in an attempted robbery in broad daylight.

The woman raced to give first aid when she saw a group of bystanders gathered around the victim as he lay covered in blood in the quiet residential road in Enfield at 7pm last night.

Paramedics from the London Air Ambulance performed emergency surgery at the scene in Lackmore Road but he was pronounced dead from a single stab wound to the chest some 30 minutes later.

Three 18-year-olds were today being held in police custody on suspicion of murder.

Neighbours today told how they attempted to give the 28-year-old CPR on a grass verge at the roadside.

His body was covered with a white bedsheet for around two hours before a white forensic tent was erected to shield his body from view.

Surrounding roads were closed for several hours as the investigation continued into the early hours. A black Volkswagen Golf was removed from the scene just before 1am.

It comes after a man was stabbed in the neck in the early hours on Wednesday less than half a mile away.

A woman in her 40s, who lives nearby with her teenage son, told the Standard: “I saw a crowd of people shouting for help and asking if anyone knew first aid. I’m a qualified first aider and I couldn’t walk away and ignore what was going on.

“I began to do CPR on the young lad and his friend was next to me applying pressure to the stab wound. He kept on asking me to carry on pressing and thanked me continuously.

“I was doing CPR on him and waiting for the ambulance to arrive."

She added: “People were saying he had been stabbed after a fight broke out and the weapon was a flick knife.

“I remember that when it was just me and that one paramedic trying to saving him we had got his heart rate up to 147 and I had a slight feeling that we might be able to save him, but I knew deep down that he was gone.

Another neighbour said: “I could see four black males fighting and I didn’t really take much notice. It wasn’t until I went to my car when I saw a man on the floor, lying so still."

A Scotland Yard spokesman said police were called to the scene at 6.55pm and detectives are pursuing attempted robbery as a potential line of inquiry.

He said: “Officers, London Ambulance Service and London’s Air Ambulance attended the scene and discovered a man, believed aged 28, suffering a stab injury. He died at the scene at 7.31pm.”

Police have appealed for witnesses to contact the incident room on 0208 345 3706.