The truck first hit an autorickshaw and then ran into another one after crashing against a van as one of its tyres exploded, the police said.
The victims killed in the mishap included eight men and seven women, all hailing from Kalaburagi district in north Karnataka and were travelling in the autorickshaws. Among the injured, seven were travelling in the van and the remaining ones in the autorickshaws.
The injured have been hospitalised in Ballari. Police said the victims were construction workers on way to their native place from Bengaluru.
Rampura is about 80 km from Chitradurga and 260 km from state capital Bengaluru towards Bellari in the state's northwest region.
"The husk-laden truck was on way to Bengaluru from Bellari via Chitradurga while the tempo was going to Molkalkur. The truck driver fled the spot," Rampura Inspector Sridar Shastri told IANS.
A case has been registered against the absconding driver and truck owner and the vehicle has been seized.
Earlier, Chitradurga District Superintendent of Police M Arun Rangarajan told IANS that 11 of the victims died on the spot. The three others succumbed to serious injuries in a state-run hospital at Bellari.
"The injured have been rushed to the Vijayanagara Institute of Medical Sciences at Bellari," said Mr Rangarajan.
(With inputs from agencies)