Three youths died and six others were injured when their motorcycles clashed head-on with a pickup truck during their races on the road from Larnsak to Nongcharngket in Larnsak district of Uthai Thani province yesterday.
Larnsak police said about 50 motorcycles gathered on the road in the afternoon before starting the race.
Some racers were seen in stunt riding by lifting the front wheels up when they started the race, a witness told police.
But unexpectedly a pickup truck came out on their way and clashed head-on with the racing bikes.
One racer died on the spot while nine others were injured, two critically.
They were admitted immediately to Larnsak hospital where two others died upon arrival, one of them a six-month pregnant girl, believed to be pillion rider.
Police said they were looking into CCTV cameras in the area to summon the racers for questioning.
Three young bike racers die in crash with truck - Thai PBS English News