A fatal accident that resulted in two spectators killed and more than ten others injured, occurred on the third lap of the X Gran Premio de Penya Rhin, a non-championship Formula 1 race held at Pedralbes street circuit in Barcelona, Spain, on Sunday, 29 october 1950.

About 11h10, the Italian driver Franco Rol lost control of his Maserati 4CLT/48 bearing the race number #36 and crashed, ending into a crowd. Many spectators suffered injuries and were taken to local hospitals including the Hospital Clínico de Barcelona, where two of them were pronounced dead.

The two victims who were identified only hours after the accident, were:
- Secundino Sánchez Navarro, a 32-year-old single man from Valladolid province who lived in Barcelona, working in a local foundry.
- Carmen Laguna de Lomas, 45-year-old, who was watching the race along with her husband, engineer Arturo Mas Sardá, 48, also severely injured and their son, Arturo, 12.
Amongst the other nine injured spectators, only Joaquín Boix Juliachs, 18, and José Vallyer de Mariné, 70, were listed in critical condition.

The race was not stopped and eventually Alberto Ascari in a Ferrari 375 won the race, from team mates Dorino Serafini, second and Piero Taruffi, third. Owing to the fatal accident, the prizegiving ceremony and the subsequent banquet to celebrate the victory was canceled by the organisers.

R.I.P