Sabu, hailing from nearby Kundara, was standing near the jeep belonging to the State Labour Department when the explosion occurred, police said.
He has come to the court in connection with a case.
Preliminary findings showed the explosion was caused by a 'steel bomb' (explosives packed in steel pipe) planted beneath the parked vehicle, which was partially damaged under the impact of the blast, police said.
Sabu suffered injury in his eye and nose and his condition was not serious, police said adding he had been hospitalised.
Bomb squad and other forensic officials are at the spot. Police said they recovered gelatin sticks and 17 batteries and fuse materials from the jeep.