* Rosberg wins race marred by tyre failures
* Vettel fails to finish
* Home victory escapes Hamilton (Adds detail, quotes)
Germany's Nico Rosberg won the British Grand Prix for Mercedes on Sunday after a spate of exploding tyres almost caused the race to be stopped and threw the sport into crisis.
Rosberg's second victory in three races fell into his lap on a bright and breezy afternoon in which team mate Lewis Hamilton's hopes of a home victory from pole position were extinguished early on in a flash of flailing rubber.
The German took the lead 11 laps from the end when the Red Bull of triple world champion and compatriot Sebastian Vettel suffered a rare mechanical breakdown and rolled to a halt.
"When Sebastian stopped, I won't lie. I wasn't disappointed by that one. And it was just a great race from then," added the German, who beat Red Bull's Mark Webber by 0.7 seconds after a thrilling last seven laps following the second safety car.
Ferrari's Fernando Alonso, who had qualified ninth after what he said was his worst Saturday of the season, swooped in to take third place and cut Vettel's lead to 21 points.
Vettel has 132 to the Spaniard's 111 after eight of 19 races, with the German's home race at the Nuerburgring next up in a week's time.
Mercedes moved up to second in the constructors' championship, 48 points behind Red Bull.
Webber, who started on the second row but plunged to 14th at the end of the first lap after a nightmare start, continued a run of Silverstone podium finishes dating back to 2009.
"It's a very, very special day," said Rosberg, who added to his Monaco win with his third career success.
"With Lewis, I feel sorry for all the British fans. It would have been a great race for Lewis here in front of his home crowd. That's racing sometimes," declared the German in a podium interview with 1996 champion Damon Hill.
Webber, in his last British Grand Prix, said it "would have been about a hundred cherries on top if I'd managed to get past him but I didn't. He deserved the win and we made him work for it which was good and rewarding.
"But we could have got much more out of the car in the race today to be honest."
Hamilton, chasing his first win for Mercedes since his move from McLaren, led for the first eight laps until the 2008 world champion's rear left tyre burst.
He nursed his bucking car around the circuit, with only two wheels in regular contact with the track, pitted in 18th place and returned to the race in 21st place.
It was the start of a mighty drive by the Briton, who ended the race in fourth place with the crowd applauding his performance.
"Wonderful drive, Lewis," said team principal Ross Brawn over the team radio at the finish. "Sorry it didn't quite work out but well done."
Hamilton's blowout was the first of five rear left failures in a race with two safety car stints as marshals collected debris - the last caused by Vettel's car being stranded on the pit straight.
"Lost the drive, lost the gearbox," the German shouted over the radio.
Ferrari's Brazilian Felipe Massa, Frenchman Jean-Eric Vergne in the Toro Rosso and Mexicans Esteban Gutierrez and Sergio Perez for Sauber and McLaren respectively also suffered tyre failures.
"It was quite close to being red flagged. It did occur to me to do that," race director Charlie Whiting told reporters.
Red Bull said they found cuts in Vettel's tyre after he had pitted while Mercedes detected the start of delamination in Rosberg's rear left.
"We have seen something new, a different type of problem. We're currently performing our analysis, we've got to go away and understand what has happened today," said Pirelli motorsport director Paul Hembery.
"It was one tyre at the back, left rear, so we need to understand that. It's pointless me adding anything else until we have all the facts."
Massa, who suffered a near-fatal head injury in Hungary in 2009 when hit on the head by bouncing debris, went to the back of the field after he pitted on three tyres and a rim but also fought back to finish sixth, behind Lotus's Kimi Raikkonen.
Raikkonen set a Formula One record for his 25th successive points finish, breaking the previous milestone held by Michael Schumacher.
Germany's Adrian Sutil was seventh for Force India with Ausralian Daniel Ricciardo, one of the candidates to replace Webber next season, eighth for Toro Rosso.
Britain's Paul Di Resta was ninth for Force India, after qualifying fifth on Saturday and then being demoted to the back row of the grid when his car was found to be underweight.
Germany's Nico Hulkenberg took the final point for Sauber, with former champions Williams finishing empty-handed for the ninth race in a row. Their Venezuelan driver Pastor Maldonado was 11th.