The 44-year-old cyclist, travelling on a blue mountain bike, died after the collision on Petersfield Road involving a white BMW at 2.15pm.
Despite the efforts of passers-by and emergency services the cyclist was pronounced dead at the scene.
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His next of kin have been informed and are being supported by specialist officers.
Sgt Paul Stenton, said: ‘Investigations into the exact circumstances of the collision are ongoing and we are keen to speak to anyone with any information.
‘Were you in the area at the time? Did you see a blue pedal cycle or a white BMW in the run up to the collision or maybe you have dash-cam footage?’
Anyone with information should call 101 quoting 44220110846 or Operation Grant.
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Alternatively contact Crimestoppers online or by calling anonymously on 0800 555 111.