Police are appealing for help from members of the public to identify a cyclist who was involved in an altercation with a man in Bushy Park, Teddington.
Officers were called at 13:38hrs on Saturday, 28 December to reports of an altercation at the park.
London Ambulance Service also attended and found a man in his 60s suffering from a serious leg injury.
He was taken to hospital with injuries that were not life threatening, although they required surgery.
The victim was injured following an argument with an unknown male cyclist in the park.
Following the incident, the suspect cycled off.
The suspect is described as a white man, aged 30-40 years, tall and of large build, clean shaven and speaking with a London accent.
At the time of the incident he was wearing a grey tracksuit with blue stripes and was riding a mountain bike.
Officers are keen to hear from anyone who thinks they know the identity of the suspect.
Anyone with information is asked to call police on 101 quoting 3234/28DEC or tweet @MetCC. Alternatively, contact Crimestoppers anonymously on 0800 555 111.