Paula Radcliffe won her third London Marathon victory in as many attempts with a superb performance.
The world record holder crushed her rivals with a time of two hours, 17 minutes and 41 seconds, over five minutes ahead of Constantina Dita.
Kenya's Martin Lel was the surprise winner in the men's race ahead of world champion Jaouard Gharib, with Britain's Jon Brown a creditable sixth.
Saul Mendoza and Francesca Porcellato defended their wheelchair titles.
UPDATES (all times BST):
1152: Kenya's Martin Lel wins the men's race in two hours seven minutes 25 seconds, ahead of world champion Jaouard Gharib of Morocco and South Africa's Hendrik Ramaala. Britain's Jon Brown sets a personal best of 2.09.35 in sixth.
1146: After 40kms, Martin Lel leads by 14 seconds from Jaouard Gharib and South Africa's Hendrik Ramaala. Britain's Jon Brown has overtaken the toiling world record-holder Paul Tergat in sixth.
1144: Britain's Jon Brown is on track for a personal best. He is running alongside Olympic champion Stefano Baldini.
1142: Martin Lel is setting about breaking his better-known rivals. World champion Jaouard Gharib of Morocco is trying to chase him down but the Kenyan looks comfortable.
1136: Kenya's Martin Lel makes a sudden break and quickly moves away from the big names in the chasing group.
1133: Last year's champion Evans Rutto is the first of the men's contenders to begin to drop off the leading group.
1120: Francesca Porcellato makes it a hat-trick of titles in the women's wheelchair race - denying Dame Tanni Grey Thompson a seventh London win. Thompson finishes a distant third.
1117: Paula Radcliffe wins her third London Marathon in a time of two hours, 17 minutes and 41 seconds, the third fastest time ever.
1110: The crowds are roaring on Paula Radcliffe as she heads up The Mall en route to a convincing victory.
1100: Mexico's Saul Mendoza breaks away from the pack in the closing stages to win the men's wheelchair race in 1:35.52. Canadian Jeff Adams is second with Britain's David Weir in third.
1057: Radcliffe picks up her pace again and is now almost three minutes ahead of second-placed Constantina Dita.
1051: Radcliffe stops momentarily by the side of the road to empty her bladder but is soon back in her running again.
1044: The men's race continues to be a cagey affair, with the favourites happy to stay behind the pacemakers.
1040: Radcliffe's 19th mile is her slowest so far but she maintains a lead of over two minutes from second-placed Constantina Dita and only a disaster will stop her claiming a third London title.
1035: Radcliffe looks to be struggling a little as her head begins to bob - but she can afford to ease off the pace with the lead she has.
1031: British pair David Weir and Tushar Patel are challenging Saul Mendoza for the lead in the men's wheelchair race.
1018: Heartbreak for Gunilla Wallengren in the women's wheelchair race as she suffers a puncture, putting her out of contention. Italy's twice champion Francesca Porecellato now leads, but Dame Tanni Grey Thompson is in touch.
1011: Radcliffe's halfway time is confirmed at 68 mins 27 seconds - the fastest half-marathon in the world this year. Romania's Constantina Dita moves into second as Kenyan duo Margaret Okayo and Susan Chepkemei pay for their early pace.
1010: In the men's wheelchair race, defending champion and favourite Saul Mendoza continues to be challenged by a group of six.
1005: Radcliffe goes through the halfway point faster than any woman other than herself has done before.
1000: The men's race goes through three miles at average pace. A group of 15, including two pacemakers, are leading the way. In the women's race, Radcliffe is approaching Tower Bridge for the first time.
0952: Paula Radcliffe now has a 28-second lead over 2004 champion Margaret Okayo in second place after 15kms.
0949: Last year's winner Saul Mendoza is in a leading group of seven as the men's wheelchair race crosses the Mall. In the women's race, Sweden's Gunilla Wallengren has made a break, leaving rivals including Dame Tanni Grey Thompson trailing.
0947: The 'fun' runners follow the elite men through the start line. A record 31,000 participants will compete this year.
0945: Sir Steve Redgrave, who is running the marathon wearing the number 2012 to promote London's Olympic bid, starts the men's race.
0937: World record holder Radcliffe strikes for the lead, leaving both Okayo and Chepkemei trailing.
0931: Radcliffe goes past the Cutty Sark, having reached 10km in 32 minutes 17 seconds. Last year's winner Okayo already seems to be finding the pace too hot and is dropping back.
0925: The men's and women's wheelchair races begin.
0918: Radcliffe is receiving plenty of support along the course. She is in a leading group of five which also includes Okayo and Chepkemei plus the two pacemakers.
0912: Radcliffe, wearing white gloves, loses one of her pacemakers as she continues to set a demanding pace. Kenyan duo Margaret Okayo and Susan Chepkemei are in the chasing group.
0905: Radcliffe is already out front, running alongside two pacemakers, and goes through the first mile in just over five minutes.
0900: Double Olympic champion Haile Gebrselassie gets the women's race under way.