Red Bull driver Sebastian Vettel won an eventful Korean Grand Prix on Sunday to close in on his fourth straight Formula One championship.

The German led throughout the race, but two safety-car periods and significant graining on his tires made for a hard-fought win.

He finished 4.2 seconds ahead of Lotus' Kimi Raikkonen, who was just ahead of teammate Romain Grosjean.

Vettel now leads the drivers' championship by 77 points with only five races remaining and looks increasingly certain to win the title.