SPA-FRANCORCHAMPS, Belgium - Red Bull's Sebastian Vettel dominated the 2013 Belgian Grand Prix to stretch his overall lead to 46 points with eight races remaining in the Formula 1 season.Ferrari's Fernando Alonso, now his closest rival, finished second - a hefty 16.8 seconds behind - after starting ninth. Vettel has 197 points after the his fifth win of the 2013 season. Alonso has 151 points.Image galleryBefore the race, protesters from the environmental group Greenpeace staged a demonstration against race sponsor Shell's plans to drill in the Arctic.'ARCTIC OIL? SHELL NO!'Two paragliders flew over the circuit, trailing a banner, and others then climbed onto the grandstand roof and unfurled a 20-metre banner that read "ARCTIC OIL? SHELL NO!"Greenpeace international executive director Kumi Naidoo said: "I was a fan of Grand Prix racing when I was growing up, but I am not a fan of what Shell is doing in the Arctic."Right now we are in the race of our lives against Shell, a company that sees the melting of the Arctic as a business opportunity, rather than a warning."There were boos and cheers from the crowd as drivers stood on the podium after the race, although reports suggested that the jeers may have been directed at protesters trying to interrupt.Vettel commented: "We were a bit confused because the crowd are booing and cheering and I'm not sure why."Click here for the 2013 Belgian grand prix race results!QualifyingThird practiceSecond practiceFirst practiceStay with Wheels24 for the 2013 Belgian GP weekend.