A cyclist accused of killing a Lewisham mum after hitting her on his racing bike started shouting at her as she lay mortally injured, a court heard.

Charlie Alliston was allegedly going 18mph on a bike with no front brakes when he crashed into 44-year-old Kim Briggs as she crossed Old Street in Islington on February 12 last year.

Alliston, then aged 18, was wearing a t-shirt with the words “Anti Social” emblazoned on them when he hit the mum-of-two with his bike, which had no front brakes.

Now 20, he is on trial at the Old Bailey in a legal first for manslaughter and causing grievous harm by wanton and furious driving under the 1861 Offences Against the Person Act.

Witness David Callan was walking along Old Street at about 12.15pm that day when he looked up and saw the crash, according to a statement read in court.

He said: "I had my head down looking at something on my mobile phone when I heard a shout.

"It was a loud shout and seemed like a male voice conveying urgency like a warning or alert.

"It made me look up immediately, just in time to see a collision between a cyclist and a pedestrian.

"The cyclist flew through the air and the pedestrian fell at the point of impact.

"The cyclist clattered to the ground further down the road but quickly sprang to their feet and shouted something at the pedestrian as they took a step towards the pedestrian who lay on the ground.”

Crash investigator Edward Small, who studied CCTV of the incident, concluded Alliston would have been able to stop and avoid collision if the bike had been fitted with a front brake.

He was a minimum of 6.65 metres away as Mrs Briggs stepped out into the road when he swerved and tried to take evasive action, the court heard.

Tests on a conventional mountain bike found a stopping distance of around three metres but Alliston's model was four times longer, at some 12 metres, the court heard.

Alliston's "fixie" bike was not legal to use on the road without it being modified to add a front brake, jurors have heard.

Speaking for the defendant, Mark Wyeth QC suggested that Alliston had the right of way as the lights on the stretch of Old Street were green and Mrs Briggs could have avoided danger by using a pedestrian crossing less than 10 metres away.

In a police interview, Alliston insisted he thought Mrs Briggs would stop after he shouted out to her.

In transcripts read in court, he said: "I have warned her to stop. I thought she would stop but she didn't. That's all I can say. That's all I can remember."

Asked why he did not have front brakes fitted, he said: "I feel safe. I feel comfortable controlling my own speed."

Alliston went on to say he did not stand by an internet post under his username CharlieF***ingA that he made shortly after the crash.

In a post on a news website, Alliston said the crash was not his fault as he had shouted out to warn the pedestrian, but she acknowledged his presence then "proceeded into the road and looked back at her phone".

Alliston, of Trothy Road in Bermondsey, denies the charges against him. The case continues today (August 16) at 2pm.