It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Portsmouth: Police Officer Dies In Cycle Race Accident
A Hampshire police officer has died after he was involved in an accident during a cycle race at a velodrome.
Richard Phillips-Schofield, 33, was taking part in the race at the Mountbatten Centre velodrome in Portsmouth, Hampshire, on Sunday when the accident happened.
He was taken to the Queen Alexandra Hospital in Portsmouth with severe chest and head injuries, where he died today.
Mr Phillips-Schofield was a response officer for Hampshire Police serving at Bitterne, and was previously stationed at Portswood. He was unmarried and is survived by his parents.
A Hampshire Police spokeswoman said: "Rich's main passion was for cycling, and he started his cycling at the Light Hall School in Solihull.
"He represented the force in cycling at the highest level, winning national and international awards; most recently garnering two gold medals and a silver medal in the World Police and Fire Games in Belfast.
"The force flags at Winchester headquarters and Netley have been lowered as mark of respect, and will remain lowered throughout tomorrow.''
Superintendent James Fulton, area commander for Southampton, said: "Richard was an exceptional officer. He worked in the city for all of his 10 years' service, and was universally popular - a first class officer, thief taker, colleague and friend.
"The whole force shares the pain of his family and friends, and at this time we remember Rich as a man who inspired so many and delivered so much.''
Chief constable Andy Marsh competed at the World Police and Fire Games with Mr Phillips-Schofield in Belfast last year. He said: "I was proud to serve with Richard, and had the privilege of being one of the first of his colleagues to congratulate him on his gold medal when we competed together in Belfast last year.
"His service in the police was no less impressive, a first class officer, team player and friend to so many. He was a credit to Hampshire Constabulary and policing in many ways.
"Richard's loss will have a huge impact on friends and colleagues across the service, not only in Hampshire and the Isle of Wight but across the UK.
"Our thoughts and prayers are with his family and friends at this tragic time.''
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