Officers remain at the scene of a collision on the A4, Bath Road, Wargrave which occurred this afternoon at about 1.50pm.
The collision involved a car and motorcycle which was being ridden by on-duty police officer PC James Dixon.
Sadly a passenger in the car and PC Dixon died following the incident.
The passenger in the vehicle was a 91-year-old woman.
PC Dixon was based at Loddon Valley police station.
Next of kin have been informed.
The driver of the vehicle, a woman, was also injured in the incident and has been taken to hospital for treatment. Her injuries are not thought to be life threatening.
The road remains closed and will remain closed for the remainder of the evening and emergency services remain at the scene. We continue to advise drivers to avoid the area.
Further details will be released when it is possible to do so.
As is standard procedure, due to the fact that the incident resulted in the deaths of a member of the public and an on duty police officer Thames Valley Police has made a mandatory referral to the IPCC who have begun an investigation.