A cyclist on trial over the death of a pedestrian in Old Street was thrown through the air when the pair collided but quickly got up and began shouting at her, a court heard.

Charlie Alliston, 20, was allegedly riding a fixed gear track bike with no front brake when he crashed into 44-year-old Kim Briggs as she crossed Old Street in February last year. Mrs Briggs, a mum of two, died days later. The court heard today she had not been using a nearby pedestrian crossing.

Alliston, then 18, is on trial for manslaughter and causing grievous harm by wanton and furious driving under the 1861 Offences Against the Person Act.

At the Old Bailey this morning, prosecutor Duncan Penny QC read out a statement from eyewitness David Callan.

Mr Callan described how he was walking along Old Street at about 12.15pm on February 12.

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.”

He said HR consultant Mrs Briggs was not using the crossing some 30 feet away.

He went on: “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.

“It seemed like the same voice I heard immediately before the collision.”

Mr Callan said he saw other people had come to her aid so continued on his way.

Jurors heard Mrs Briggs suffered “non-survivable brain injuries” and died in hospital a week later.

The court has heard Alliston’s “fixie” bike had no front brake so was not legal to use on the road.

In January last year, he had bought the £700 Planet X bike second-hand for £470 telling the vendor William Ringwood he used to be a courier and wanted to use it for track cycling.

Jurors have been told that crash investigators had concluded Alliston would have been able to stop and avoid collision if the bike had been fitted with a front brake.

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.

The defendant had been travelling an average of 18mph before he spotted Mrs Briggs step out into the road, jurors heard.

He was a minimum of 6.65 metres away 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.

Cross-examining, Mark Wyeth QC asked Mr Small if there could be a margin of error in his calculations of the average speed Alliston was going before he saw Mrs Briggs.

The expert replied that any difference would only have been a “fraction of a mile per hour”.

Alliston, now 20, of Trothy Road, Bermondsey, south London, denies the charges against him.

The trial continues.

Court reporting by Press Association