A banker has died after being punched by a stranger on a night out in Blackheath.

Oliver Dearlove, 30, was assaulted in Tranquil Vale on Sunday, August 28, while out with friends from university. They tried in vain to save him after he collapsed and stopped breathing following the unprovoked attack.

Police and paramedics were called and he was airlifted to hospital but died less than 24 hours later.

Detectives have launched a murder investigation and are trying to identify a group of four white women who they believe may have witnessed the “vicious early morning assault”.

His mother, Joy Wright, from Chislehurst, south-east London, said her “perfect son” had “so much more life to live” and girlfriend of four years Claire Wheatley, who he lived with in Eltham, said he was the “kindest person” and would normally avoid altercations.

Joy told The Guardian: “He was very easygoing, lots and lots of friends, played lots of football.

“He studied hard at school. He worked for a private bank in Belgravia. He had been travelling for a year. He did what most nice people do.”

The relationship manager for private bank Duncan Lawrie played for his local football team Lord Hood FC and was set to go on holiday with friends to Las Vegas next week for a combined 30th birthday celebration.

Joy said he had met friends and had lunch, dinner and drinks on the night he was attacked.

She said: “He texted his girlfriend that he loved her around 10pm. Someone picked a fight, punched him and he fell backwards and that was it.

“I don’t think there was an altercation. I think someone said to him and his friends: ‘What are you looking at’ and that was it. I think he stopped breathing when he hit the floor. His friends gave him CPR.”

She added: “He was just perfect. I’m in a state of shock. We have friends and family here and we’re all pulling together. Sometimes I’m alright, sometimes I’m not. I’m absolutely devastated for him. [He had] so much more life to live.”

Claire said she and Oliver were saving for a house and had recently discussed having a baby together.

She said: “He was the kindest person. He was the most amazing person I’ve ever met and ever known. I’m so lucky to have known him.”

“He and his friends aren’t the kind of guys who look for trouble. They like having a good time and a bit of banter.

“But he’s just the kindest person and would normally cower away from things like that, from any altercation.”

Comedian Rob Beckett tweeted that Oliver was his best friend growing up. He urged anyone with information to contact police.

Comedian Rob Beckett grew up with the victim and has appealed for witnesses to come forward

Metropolitan police were called at about 12.45am to the scene of the attack. Oliver was taken to an east London hospital where he died at 10.22pm on Sunday night.

A postmortem will be performed on Tuesday at Greenwich mortuary.

Homicide and major crime command’s DCI Lee Watling said: “We are retaining an open mind at this stage of the investigation with regard to a motive and our primary aim is to establish how Oliver came to receive the injuries that led to his death.

“We are appealing for anyone who was in Tranquil Vale who witnessed the incident.”

Anyone with information should call the police incident room on 0208 721 4205 or Crimestoppers anonymously on 0800 555 111.