A suspected burglar put in handcuffs after his arrest attacked a woman police officer and then escaped by driving off in her car.
The female officer was driving the man to Slough police station when he forcibly took control of the car.
The man, one of three arrested on suspicion of burglary, dumped the car in Keel Drive about six minutes away.
The suspect is described as Asian, in his mid 20s and about 5ft 8in tall. He may still be wearing handcuffs.
Supt Pete Davies said: "This is a serious incident which could have led to the officer and members of the public being seriously hurt. Thankfully, neither was injured.
"I would appeal to anyone who knows the whereabouts of this man to contact us immediately."