Pol Col Wiroon Suwannawong, deputy provincial police chief, said Pol Sen Sgt Maj Poonkrit Buakaew, 46, was killed as he was trying to stop the fleeing car by shooting its tyres.
Wiroon said Surachet Wanlua, 24, was on his way with an accomplice to deliver drugs to an undercover officer and police planned to arrest the two in a sting operation.
When they tried to nab them, however, Surachet increased his speed, hit Poonkrit and drove off. As police were busy trying to stop the fleeing car, the other suspect fled into a roadside palm oil plantation and disappeared.