Three people were injured and four vehicles burned out when a tractor-trailer smashed into 12 vehicles on the elevated bypass above Ramkhamhaeng Road in Bang Kapi district late on Tuesday night.
The accident occurred around 10.20pm on the downslope of the outbound section of the elevated road, heading towards Lam Salee intersection.
The four vehicles burned and destroyed were a Honda City, Toyota Avanza, Toyota Altis and BMW 520.
Firefighters took only 15 minutes to put out the flames once they arrived.
Two men and a woman were injured and weretaken to Kasemrad Ramkhamhaeng and Phaet Panya hospitals by first responders. The extent of their injuries was not reported.
Other damaged vehicles included cars, a taxi, a passenger van and a 10-wheeler.
Suwachat Pruprong, 24-year-old driver of the 18-wheel trailer truck, told police that a motorcyclist cut in front him, causing him to swerve and lose control. Braking was only partially effective on the downslope, he said.
His truck, with a heavy load of gravel, hit the taxi which in turn smashed into the other vehicles. Police detained him for a drug test.
Police closed the elevated road to remove the damaged vehicles.
Kitja Jansukcharoenjinda, the 50-year-old driver of the passenger van, said the truck hit the left side of his packed van before smashing into the taxi and other vehicles. He backed his damaged van out onto the elevated road as other vehicles caught fire.