A teenage racing driver who lost part of both his legs after a horror crash has thanked emergency workers for "saving my life".

Billy Monger, 17, underwent the amputations after his Formula 4 car hit a stationary vehicle at 120mph during a race at Donington Park on April 21.

More than £750,000 has been donated to an online fundraising appeal set up following the crash, with Formula 1 stars Lewis Hamilton and Jenson Button among those backing the appeal.

In a statement posted on Twitter, Billy said a "huge thank you" to everyone who had helped and supported him since the collision.

"Your kind words have given me and my family the strength to get through this past week," he said.

"The love and generosity of our motorsport family, fans, and everyone that has supported me is awesome and truly inspirational.

"The marshals, medics, doctors, air ambulance and extraction crews at Donington along with all the staff at Queen's Medical Centre - what can I say? Without you guys I wouldn't be here today!

"I will always thank you all for saving my life!"

Billy reserved special praise for his sister, Bonny, for being his "true hero" and giving him "the will to keep fighting".

Onboard footage from a camera mounted on Billy's JHR car during the race showed him crashing into the back of Finnish driver Patrik Pasma's car, which appeared to have stopped on the track.

The teenager was trapped in his car for 90 minutes before being airlifted to the nearby Queen's Medical Centre in Nottingham.