RideLondon-Surrey: Two riders hurt in separate crashes
Two riders have been injured in separate crashes during the amateur RideLondon-Surrey 100 cycle event.
A man came off his bike and hit a tree just after 09:00 BST in Woking and was taken to hospital by air ambulance.
Another rider was injured in Thames Ditton just before 11:00 and treated at the scene for head injuries.
Belgian Tom Boonen later won the men's professional Prudential RideLondon-Surrey Classic race, which finished in The Mall, London just before 18:25.
The ride which began from Horse Guards' Road in James's Park went through Leatherhead, Oxshott and Esher in Surrey before heading back to the capital.
Up to 150 professional cyclists, including Tour de France winner Chris Froome, took part in the race.
Following the first crash, an air ambulance was sent to the scene, and a "contingency route" between West Byfleet and Ripley was opened so the event could continue, RideLondon tweeted.
The cycle ride was disrupted for 45 minutes between Pyrford and Ripley in Surrey.
Before the diversion was lifted, some riders reported being held stationary for 45 minutes, BBC Surrey's Peter Stewart said.
The injured cyclist was taken to St George's Hospital, Tooting, where is condition is described as serious.
The second cyclist was injured when he came off his bike in Thames Ditton just before 11:00, the South East Coast Ambulance Service said.
He was treated for a head injury by the air ambulance paramedics.
Emergency road closures around Old Woking were later lifted, Surrey Travel tweeted.
The 200km (125-mile) Classic was paused due to congestion in Dorking High Street caused by riders in the 100 event having been delayed after the earlier crash, RideLondon said.
The organisers also said that because of the "backlog" of riders in the RideLondon-Surrey 100 race they had put out a diversion that cut out Box Hill in Surrey.
Box Hill has become a popular attraction for cyclists, particularly after it featured prominently in the London 2012 Olympic cycling road race.
RideLondon tweeted: "Following the incident near West Byfleet when a rider required an air ambulance, a backlog of riders built up on the route.
"In order to ensure all riders [of the 100 race] get to the finish line within the required 8.5 hours, a planned diversion route has been opened at Mile 44 to divert those riders through to Mile 70 (taking out Box Hill and rejoining the route before Leatherhead)."
The national cycling team from Rwanda is taking part in the race for the first time.
The BBC has apologised after losing some pictures during transmission as the lead riders completed the final minutes of the course.
"We are very sorry if some technical issues affected people's enjoyment of the race and we are looking into what happened," a spokesman said.