Thieves stole a Jeep after reaching through the letter-box of an Oxfordshire home and taking the vehicle's keys.
The offence happened in Pudsey Close, Abingdon, between 2330 GMT on 30 January and 0845 GMT on 31 January.
Police found the car on fire in Peep-o-Day Lane, a few hours later.
Pc Paul Reece appealed for witnesses to come forward. He added: "I would like to remind residents to keep their car keys in a safe place."