Metropolitan Police Commissioner Pol Lt Gen Kamronwit Thoopkrajang Monday vowed to step down if he fails to arrest the driver of a luxurious sport car that hit and killed a patrol policeman and fled the scene.

Pol Sen Sgt Maj Wichien Klanprasert of Thonglor police station was hit by a black sport car at the mouth of Soi Sukhumvit 47 early Monday. The car, whose make and license plate were not known, dragged Wichien's body and motorcycle for over 200 metres.

Witnesses told police that the car fled into a house on Soi Sukhumvit 53. The house is owned by Chalerm Yoowitthaya, an executive of Red Bull energized drinks.

Kamronwit visited the house later Monday and exit the house one day later.

He said he would seek a court warrant to search the house because a taxi motorcyclist saw the car entering the hosue.