The accident happened last evening, they said.
One charred body has been identified as 36-year-old Hariram, the Rajgarh police said.
Six fire extinguisher vans were put in action to douse the fire in two trucks till late night yesterday, they said.
One of the truck was loaded with slabs, while other one carried pipes, they said.
The injured person, Balmukund, was rushed to a nearby hospital, they added.
Alwar-Sikandra Mega highway was blocked for couple of hours but the traffic was eased out by midnight, they said.