The court also imposed a penalty of Rs 5,000 each on the convicts yesterday, prosecution sources said.
Eleven other accused were acquitted of the charges due to lack of evidence, they said.
In January 2002, the accused -- Ramprakash, Dinesh, Ram Singh and Alwar -- had attacked the police team which had gone to conduct a raid on their house in Nagla Bhavani village of the district, injuring some policemen.
They had also looted some rifles, which were later recovered by the police.