New Delhi - Tension simmered in pockets of India's Communist-ruled eastern state of West Bengal Saturday as six people died in clashes between staff of rival political parties, news reports said.

Four people were killed in the area of Uluberia in Hooghly district in a clash between workers of the ruling Left Front and the opposition Trinamool Congress, a regional party, the NDTV television channel reported.

In Nandigram in East Medinipur district, which has seen ongoing violence over the acquisition of farmland for an industrial hub by the government, two people were killed in a similar clash. Police said they suffered gunshot wounds.

Elections were held in both areas Thursday in the penultimate phase of India's month-long general elections.

The West Bengal government was forced to withdraw its chemical hub plans for Nandigram in 2008 after prolonged protests and violence.

However, simmering tension between rival political parties has continued in the area which saw heavy deployment of security forces for Thursday's election.

Police have been withdrawing since Friday for redeployment in West Bengal's capital Kolkata and other parts of the state where elections are scheduled to be held in the last phase on May 13. (dpa)