Two riders have died after a “catastrophic” 11-bike crash on lap one of a British Supersport Championship race at Oulton Park in England on Monday.

The season-opening feature race, supporting the top-level Superbikes and broadcast live on TV, was red-flagged and the event abandoned following the “chain reaction incident” exiting the first turn.

Owen Jenner, 21, and New Zealand father-of-two Shane Richardson, 29, could not be saved while 47-year-old Tom Tunstall was taken to hospital with significant injuries.

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“Jenner was initially treated trackside and then taken to the circuit medical centre, where despite further resuscitation treatment, he died from a catastrophic head injury,” organisers said in a statement.

“Richardson was initially treated trackside and then taken to the circuit medical centre before being transferred to Royal Stoke University Hospital with severe chest injuries.

“He died prior to arrival.”

Tunstall suffered serious back and abdominal injuries and is now in hospital.

Organisers said Carl Harris, Max Morgan, Cameron Hall, Freddie Barnes, and New Zealander Morgan McLaren-Wood suffered minor injuries while Lewis Jones, Corey Tinker and George Edwards escaped unharmed.

“The Motorcycle Circuit Racing Control Board and MotorSport Vision Racing are investigating the full circumstances of the incident in conjunction with the Coroner and Cheshire Constabulary,” organisers said.

Richardson is survived by partner Hannah and children Max and Maddie.

The proud Kiwi, who finished ninth in the championship last year, rode with the New Zealand flag on his No.28 Suzuki.

“Don’t know what to say,” New Zealand’s Moto3 rider Cormac Buchanan wrote.

“Shane was truly one of the best people I ever had the privilege of sharing the track with, not only a super talented rider but a down to earth person away from it.

“You never failed to put a smile on all of our faces. You were someone I could look up too and learn from and I am so lucky to have had your guidance in my first year in Europe in the UK.

“I cherish all of the track walks with you ... the hard battles we had, bumping bars and swapping paint.

“I’m grateful to have been able to consider you a competitor, rival, and a friend. I always felt your support no matter what the situation, race, or outcome was.

“To Hannah, Max, and Maddie I send you all of my love, support, and condolences. I am always riding with you, thank you for everything Shane.”

Richardson’s death comes just two years after fellow Kiwi Damon Rees died aged 28 following a short battle with illness while in England competing in the Supersport Championship.

Jenner’s death came on his father’s birthday, with the rider celebrating the occasion on social media hours before the race.

“Happy birthday to the old boy,” he wrote.

“Wouldn’t be where I am without him and I know he wouldn’t wanna be anywhere else on his special day.”

Australian rider Ben Currie, the 2023 Supersport champion, paid tribute after avoiding being caught up in the crash.

“Hard to put into words what happened today,” he wrote.

“Gutted for everyone involved. Two of our finest men lost to the sport we love. Thoughts are with all that are involved. RIP boys.”

Freddie Barnes, one of the riders hurt in the incident, wrote a message from hospital while waiting to be assessed.

“I count myself incredibly lucky. My condolences go out to Owen and Shane’s family and friends,” he wrote.

“I’m absolutely devastated, I have no words so ride on in paradise boys.

“Keep fighting Tom (Tunstall) and my thoughts are with the other riders involved.”

Other competitors mourned the losses.

“I really don’t know what to say right now. Two lads I feel absolutely privileged to call mates,” TJ Toms wrote.

“My heart like many others is completely shattered. My heart, love and thoughts go out to OJ’s family and to Hanna and Shane’s little family. Thank you for all our memories boys.”

Harry Truelove said: “No words. You will be missed.”

Joe Sheldon-Shaw wrote: “Absolute pleasure sharing the track with these gents over the years, had some great races with both these lads, and a lot of laughs off the track with OJ. Heartbreaking day today, I’m lost for words honestly. The paddock won’t be the same without them.”

The Supersport Championship season is due to resume alongside the Superbikes Championship at Donington in a fortnight.