A pile-up at the first corner took out four cars as the Belgian Grand Prix got off to a dramatic start.
The safety car was immediately deployed following the multiple collision at the La Source hairpin.
From sixth on the grid Williams' Pastor Maldonado made a jump start, but behind the Venezuelan it was the Lotus of Romain Grosjean who clipped Lewis Hamilton in his McLaren.
The rear-right tyre of Grosjean's car caught the front-left of the McLaren, sending the Briton into a spin.
The chain reaction that followed saw Grosjean run into the back of Sauber's Sergio Perez, and as Hamilton followed through, the Ferrari of championship leader Fernando Alonso was also affected.
On-board replays showed the Lotus flying over the front of the Ferrari, but fortunately no drivers were injured.
Other casualties included Sauber's Kamui Kobayashi, forcing him into the pits and dropping him to last of the 20 remaining cars after starting from second on the grid.
Maldonado was also forced to pit, dropping him to 17th, but his race was run on lap five after another incident involving the 27-year-old and after the first four laps were run under the safety car.