By Subir Bhaumik
BBC News, Calcutta
Three leading Maoist rebels in the Indian state of West Bengal have been found guilty of waging war against the Indian state.
Sushil Roy was defiant in court
Police say the three are responsible for rising violence in West Bengal.
Santosh Debnath and Patit Paban Haldar were sentenced to life in prison. Sushil Roy was sentenced to only five years due to poor health.
About 40,000 security personnel have been deployed to maintain order ahead of state elections in April and May.
A defiant Sushil Roy said after the verdict: "The whole country will go up in flames on this verdict. Our boys will not take it lying down."
The three men also issued a statement calling for a boycott of the state assembly elections.
A fourth man, Zakir Hussain, was found not guilty.
West Bengal's elections are being held in five phases.
Most security personnel are being deployed in three districts, Purulia, Bankura and West Midnapore.
Sushil Roy, 72, is the nephew of the legendary Bengali revolutionary Dinesh Gupta.