Nico Rosberg controlled a crash-strewn Monaco Grand Prix to take his first win of 2013 ahead of Red Bull's Sebastian Vettel and Mark Webber.
The Mercedes driver led throughout as the race was interrupted by a safety-car period and a red-flag stoppage following two heavy accidents.
Rosberg's team-mate Lewis Hamilton dropped from second to fourth after losing out through the safety car.
Force India's Adrian Sutil took fifth from McLaren's Jenson Button.
The Englishman's team-mate Sergio Perez was running fifth but retired with five laps to go following damage caused in a collision with Lotus's Kimi Raikkonen, which gave the Finn a puncture and forced him to stop for fresh tyres.
In a chaotic final lap, Raikkonen moved up to 10th from 13th to take the final point.
Ferrari's Fernando Alonso was seventh after a poor afternoon in which he lost places in a series of passing moves by Perez, Sutil and Button.
Toro Rosso's Jean-Eric Vergne was eighth from Force India's Paul di Resta.
The difficulties for Raikkonen and Alonso were a boost to Vettel's lead at the head of the championship, which is now 21 points from Raikkonen and 31 over Alonso.
The race featured two safety car periods and a red flag stoppage following a series of crashes and collisions precipitated by the bunching of the field, caused by drivers measuring their pace to ensure their tyres lasted sufficiently to allow them to the optimum strategy.
Rosberg kept his head throughout all the chaos to pace himself to the second win of his career.
"It's amazing," said Rosberg. "This is my home, I've grown up here all my life and it's really special. The whole weekend went perfectly. I had a terrible start and I was close with Sebastian and Lewis but after that I controlled the pace.
"The car was really good, the tyres held on OK and that was really the key, so a massive thanks to the team. I'm ecstatic."
Hamilton followed him through the first part of the race ahead of the Red Bulls but dropped to fourth when he was forced to make his pit stop on the same lap as Rosberg because neither had stopped by the time the safety car came out.
World champion Vettel said he was pleased with gaining second place from Hamilton. "Overall I'm happy. We know it's difficult to overtake here. Congratulations to Nico, he had the pace and the tyres.
"We had a fantastic start but there was no room to overtake and I had to lift. I was surprised by the slow pace of the opening laps - you expect two silver arrows in front of you and we had two buses in front going for a cruise.
"They had a strategy but we did well to get past Lewis."
Perez's crash with Raikkonen was the last in a series of controversial incidents involving Perez at the chicane after the tunnel.
It came 16 laps after the McLaren driver had initially attacked the Lotus, throwing his car down the inside at the chicane on lap 53 forcing the Finn to take avoiding action and cut the chicane.
Raikkonen was able to keep the place because Perez also had to cut the chicane having braked too late to make the corner.
When Perez tried it again on lap 69, Raikkonen refused to give way and the two cars touched, damaging Perez's front wing and puncturing Raikkonen's right rear tyre.
Earlier, Alonso had been ordered to let Perez by into sixth place following an incident in which he had cut the second part of the chicane when the Mexican tried to pass him on lap 45.
The Ferrari driver argued that he had done so to avoid a collision, but the stewards ruled that the Spaniard had gained an advantage.
In the early laps, Perez had to give a place back to Button after cutting the chicane trying to pass to him.
The swap between Alonso and Perez came following a half-hour stoppage caused by a collision on lap 46 between Marussia's Max Chilton and Williams's Pastor Maldonado which damaged the barriers at Tabac corner.
Chilton appeared to move across on Maldonado, who was on the outside trying to pass the Marussia which had made a slow exit from the chicane, and the Englishman was given a drive-through penalty for causing the accident.
That incident happened only seven laps after a re-start following a safety-car period following a crash by Ferrari's Felipe Massa at Sainte Devote on lap 30.
The Brazilian's accident was almost identical to one he suffered on Saturday morning - he smashed into the barrier on the outside of the track after locking his front tyres over a bump in the braking zone for the corner.
Massa was taken to the local Princess Grace hospital but he was later released with the Brazilian confident he will be "100 per cent" for the next race in Canada.
The bunching also led to a further crash following the final safety car intervention, when Romain Grosjean drove his Lotus into the back of Daniel Ricciardo's Toro Rosso at the chicane on lap 62, bringing out the safety car for the third time.
It was the fourth accident of the weekend for Grosjean, who had twice crashed at Sainte Devote and once collided with the barriers at the chicane during the three practice sessions.
1. Nico Rosberg - Mercedes 2:17:52.056
2. Sebastian Vettel - Red Bull +00:03.888
3. Mark Webber - Red Bull +00:06.314
4. Lewis Hamilton - Mercedes +00:13.894
5. Adrian Sutil - Force India +00:21.477
6. Jenson Button - McLaren +00:23.103
7. Fernando Alonso - Ferrari +00:26.734
8. Jean-Eric Vergne - Toro Rosso +00:27.223
9. Paul di Resta - Force India +00:27.608
10. Kimi Raikkonen - Lotus +00:36.582
11. Nico Hulkenberg - Sauber +00:42.572
12. Valtteri Bottas - Williams +00:42.691
13. Esteban Gutierrez - Sauber +00:43.212
14. Max Chilton - Marussia +00:49.885
15. Giedo van der Garde - Caterham +01:02.590
16. Sergio Perez - McLaren retired, 72 laps
17. Romain Grosjean - Lotus retired, 63 laps
18. Daniel Ricciardo - Toro Rosso retired, 61 laps
19. Jules Bianchi - Marussia retired, 58 laps
20. Pastor Maldonado - Williams retired, 44 laps
21. Felipe Massa - Ferrari retired, 28 laps
22. Charles Pic - Caterham retired, 7 laps