A bomb squad on Saturday disposed of country-made bombs found by police last night in the Nanur area of Birbhum district.
The incident took place during the fourth phase of polling in the state.
On the other hand, four people have been killed in firing by Central Forces during polling in the fourth phase in Mathabhanga in the Sitalkurchi constituency in the Cooch Behar district on Saturday.
Voting for 44 constituencies in West Bengal's fourth phase Assembly elections began at 7 am on Saturday amid tight security.
This phase of the elections will witness an intense battle between 373 candidates in 44 constituencies of the state across five districts - Cooch Behar, Alipurduar, South 24 Parganas, Howrah and Hooghly.