Robbers stole charity collections from a 71-year-old man in Cookham Road last night.
The man was returning from a bonfire fundraiser in Cookham at about 8.30pm when three robbers approached his car.
They were armed with what is believed to be a broken garden ornament.
The robbers damaged the vehicle and assaulted the man before leaving with the large sum of cash.
The victim attempted to chase the men, who were described as wearing dark clothing, but they got away on foot.
Paramedics treated the victim for injuries to his face and head.
Thames Valley Police are appealing for anyone with information to contact DC Ali Marman on 101 or Crimestoppers on 0800 555111.
Top Ten Articles
CCTV images have been released of men police would like to speak to in connection with a homophobic attack on a couple as they took a train home from a Valentine's Day meal.