Spanish Moto2 rider Luis Salom has died following a crash during a free practice session at the Catalunya Grand Prix on Friday.
The 24-year-old SAG Team rider was taken to hospital and underwent surgery, but succumbed to his injuries.
"It is with great sadness that we have to report the passing of Luis Salom," MotoGP said in a statement.
"Despite the best efforts of the trauma team, he passed away at 16:55 local time."
Messages of condolence quickly started streaming in on social media.
Tennis star Rafael Nadal wrote: "Very sad news. Although words can't bring comfort in times like this, all my support goes to Luis Salom's family and friends."
Muy triste por la noticia de Luis Salom. Aunque en estos momentos ninguna palabra reconforta, todo mi apoyo y ánimo a la familia y amigos.
— Rafa Nadal (@RafaelNadal) June 3, 2016
Spanish Formula 1 driver Fernando Alonso: "Such terrible news. Such anger and sadness. Rest in peace, rider. A huge embrace to Luis Salom's friends and family."
Que mala noticia. Que rabia. Triste. Descansa en paz Piloto. Un abrazo grande a la familia y amigos de Luis Salom.
— Fernando Alonso (@alo_oficial) June 3, 2016
Two-time MotoGP world champion Marc Marquez: “Hard blow for all the World Championship. We will always remember you. #RIPLuisSalom”
— Marc Márquez (@marcmarquez93) June 3, 2016
British MotoGP rider Cal Crutchlow: "So saddened of what happened today in Barcelona."
So saddened of what happened today in Barcelona. RIP Luis Salom #39
— Cal Crutchlow (@calcrutchlow) June 3, 2016
British MotoGP rider Scott Redding: "My love and heart is with Luis Salom and his family. We lost another great rider. RIP Luis."
My love and heart is with Luis salom and his family. We lost another great rider. R.I.P Luis ? pic.twitter.com/eZXf8SU8rQ
— ReddingPower #⃣4⃣5⃣ (@Reddingpower) June 3, 2016
MotoGP said Sunday's race at the Circuit de Catalunya will go ahead, but with a revised track configuration.