London - Priscah Jeptoo took advantage of a fall by Ethiopia's Olympic champion Tiki Gelana to give Kenya their third successive victory in the women's race at the London Marathon on Sunday.
Ethiopian Tsegaye Kebede made up for missing out on the Olympics and destroyed Kenyan hopes of retaining the men's title by overhauling 2011 winner Emmanuel Mutai in the closing stages to win in two hours six minutes and four seconds.
People turned out in force in the sunshine to support the elite athletes and some 36,000 fun-runners taking part in the London event which took place six days after the Boston Marathon bombings.
A 30-second silence was held before the men's race and mass start and many of the competitors had black ribbons pinned to their tops in honour of the three dead and over 170 injured in Boston.
Women's pre-race favourite Gelana collided with wheelchair athlete Josh Cassidy at a drinks station at 15 km and had dropped off the pace by the halfway mark of the 42.195-km race, eventually finishing 16th.
Jeptoo, second to Gelana at the London Olympics, was always up with the front runners and, after a cagey first half, the 28-year-old pulled away from compatriot and world champion Edna Kiplagat after 30km.
Her arms flailing as she ran alone up the Mall to the finish, Jeptoo crossed the line in 2:20:15. Draped in a red towel, she dropped to the floor, palms together in front of her in prayer.
"I knew this morning I was going to run well and there was such a good field you were always worried someone would do better," Jeptoo told reporters.
"It wasn't until 25 miles that I got that confidence back and felt I could win."
Last year's runner-up Kiplagat was second again, over a minute behind Jeptoo and Japan's Yukiko Akaba took a surprise third place.
Up until the final couple of kilometres of the men's race, it looked as though Kenya would have cause for a double celebration.
Mutai had gone to the front ahead of compatriot Stanley Biwott after 35 km but Kebede, almost a minute down on the leaders, found a second wind and timed his attack to perfection.
The diminutive Ethiopian, not selected for the 2012 Olympics, worked his way through the field and, with his fists pumping up high under his chin, he strode past a visibly tiring Mutai in the final kilometre.
Mutai staggered over the line for second and Ethiopia's Ayele Abshero took third place. Olympic champion Stephen Kiprotich from Uganda found the pace tough and finished sixth.
"I had a little pain in my side during the early part of the race but as time went on, it got better and better," Kebede, third last year, told reporters.
"I could feel myself getting closer and closer to Mutai and that made me stronger."
Britain's Olympic 5,000 and 10,000 metres champion Mo Farah kept to his plan of dropping out of the race at halfway, stepping off the course to cheers from the large crowd lining the street.
Farah, running in distinctive blue arm socks which went from his wrists to just below his shoulders, was using his appearance to learn about the race in preparation for his marathon debut in London next year.
"I've learnt the biggest lesson of my life. If I had come here next year and made a mess of it, mentally I don't think I could have dealt with that," he told the BBC.
American Tatyana McFadden won the women's wheelchair race to add to the Boston Marathon title she won on Monday and Australia's Kurt Fearnley took victory in the men's race to end Briton David Weir's hopes of a record seventh title. Weir finished down in fifth.